Security clearance - AbsoluteAstronomy.com

For use by the United Nations
United Nations
The United Nations is an international organization whose stated aims are facilitating cooperation in international law, international security, economic development, social progress, human rights, and achievement of world peace...

, see Security Clearance (UN)
Security Clearance (UN)
A United Nations Security Clearance is a required procedure and document for United Nations staff travelling to areas designated as security phase areas, with numbers ranging from one to five ....

A security clearance is a status granted to individuals allowing them access to classified information

Classified information

Classified information is sensitive information to which access is restricted by law or regulation to particular groups of persons. A formal security clearance is required to handle classified documents or access classified data. The clearance process requires a satisfactory background investigation...

, i.e., state secrets, or to restricted areas after completion of a thorough background check

Background check

A background check or background investigation is the process of looking up and compiling criminal records, commercial records and financial records of an individual....

. The term "security clearance" is also sometimes used in private organizations that have a formal process to vet

Vetting

Vetting is a process of examination and evaluation, generally referring to performing a background check on someone before offering him or her employment, conferring an award, etc...

employees for access to sensitive information. A clearance by itself is normally not sufficient to gain access; the organization must determine that the cleared individual needs to know

Need to know

The term "need to know", when used by government and other organizations , describes the restriction of data which is considered very sensitive...

the information. No one is supposed to be granted access to classified information solely because of rank, position, or a security clearance.

Canada

Background

Government classified information is governed by the Treasury Board

Treasury Board

The Treasury Board is the Government of Canada's only statutory Cabinet committee and is responsible for the federal civil service much of the operation of the Canadian government. Among its specific duties are negotiating labour agreements with the public service unions and serving as Comptroller...

Policy on Government Security, the Security of Information Act
Security of Information Act
In Canada, the Security of Information Act is part of the Canadian Anti-Terrorism Act which received Royal Assent on December 18, 2001 and came into effect on December 24, 2001. This Act renamed and replaced Official Secrets Act 1981...

and Privacy Act. Only those that are deemed to be trustworthy and have been cleared are allowed to access sensitive information.

Checks include basic demographic and criminal record checks for all levels, and, depending on an individual appointment's requirements, credit checks, loyalty, and field checks might be conducted by the RCMP

Royal Canadian Mounted Police

The Royal Canadian Mounted Police , literally ‘Royal Gendarmerie of Canada’; colloquially known as The Mounties, and internally as ‘The Force’) is the national police force of Canada, and one of the most recognized of its kind in the world. It is unique in the world as a national, federal,...

and/or CSIS

Canadian Security Intelligence Service

The Canadian Security Intelligence Service is Canada's national intelligence service. It is responsible for collecting, analyzing, reporting and disseminating intelligence on threats to Canada's national security, and conducting operations, covert and overt, within Canada and abroad.Its...

.

Clearance is granted, depending on types of appointment, by individual Federal government departments or agencies or by private company security officers. Those who have contracts with Public Works and Government Services Canada

Public Works and Government Services Canada

Public Works and Government Services Canada is the department of the government of Canada with responsibility for the government's internal servicing and administration....

are bound by the Industrial Security Program, a sub-set of the GSP.

To access designated information, one must have at least reliability status (see Hierarchy below). Reliability checks and assessments are conditions of employment under the Public Service Employment Act, and, thus, all Government of Canada employees have at least reliability status screening completed prior to their appointment. However, Government employees by Order-in-council

Order-in-Council

An Order in Council is a type of legislation in many countries, typically those in the Commonwealth of Nations. In the United Kingdom this legislation is formally made in the name of the Queen by the Privy Council , but in other countries the terminology may vary.-Assent:Although the Orders are...

are not subjected to this policy.

Clearances at the reliability status, confidential, and secret levels are valid for 10 years, whereas top secret is valid for 5 years. However, departments are free to request their employees to undergo security screening any time for cause. Because security clearances are granted by individual departments instead of one central government agency, clearances are inactivated at the end of appointment or when an individual transfers out of the department. The individual concerned can then apply to reactivate and transfer the security clearance to his/her new position.

Security screening

Individuals who need to have RS because of their job or access to federal government assets will be required to sign the Personnel Screening, Consent and Authorization Form (TBS/SCT 330-23e).

Reliability Status (RS) - formerly known as enhanced reliability status (ERS)
- Reliability checks are done by verifying personal data, criminal records check, educational, and professional qualifications, data on previous employment and references. As well, a fingerprint check, and a credit check may be required.
- This level of clearance will grant the right to access designated documents with markings of Protected A, B & C information/assets on a need-to-know
  Need to know
  The term "need to know", when used by government and other organizations , describes the restriction of data which is considered very sensitive...
  
  basis. It is mandatory for individuals when the duties or tasks of a position or contract necessitate access to protected information and assets, regardless of the duration of an assignment.

Security assessment/clearances

Individuals who require access to more sensitive information (or access to sensitive federal government sites and/or assets) because of their job will be required to sign the Security Clearance Form (TBS/SCT 330-60e). There are three basic levels of clearance:

Confidential (Level 1)
- In addition to the RS checks, foreign employments, immediate relatives, and marriages/common-law relationships must be declared and be screened.
- This level of clearance will grant the right to access designated and classified information up to Confidential level on a need-to-know
  Need to know
  The term "need to know", when used by government and other organizations , describes the restriction of data which is considered very sensitive...
  
  basis. Department Heads have the discretion to allow for an individual to access Secret level information without higher level clearance on a case-to-case basis.
Secret (Level 2)
- Same as Confidential.
- This level of clearance will grant the right to access designated and classified information up to Secret level on a need-to-know basis. Department Heads have the discretion to allow for an individual to access Top Secret-level information without higher-level clearance on a case-to-case basis.
Top Secret (Level 3)
- In addition to the checks at the Secret level, foreign travels, assets, and character references must be given. Field check will also be conducted prior to granting the clearance.
- This level of clearance will grant the right to access all designated and classified information on a need-to-know basis.

Site access

An additional category called 'Site Access' exists not for access to information purposes but for those that require physical access to sites or facilities designated by CSIS

Canadian Security Intelligence Service

as areas "reasonably be expected to be targeted by those who engage in activities constituting threats to the security of Canada". Designated areas include Government Houses

Government Houses of Canada

In Canada, Government House is a title given to the official residences of the country's monarch and various viceroys...

, official residences of government officials, Parliament, nuclear facilities, airport restricted areas, maritime ports, and any large-scale events that are sponsored by the federal government (e.g., 2010 Winter Olympics

2010 Winter Olympics

The 2010 Winter Olympics, officially the XXI Olympic Winter Games or the 21st Winter Olympics, were a major international multi-sport event held from February 12–28, 2010, in Vancouver, British Columbia, Canada, with some events held in the suburbs of Richmond, West Vancouver and the University...

). The checks conducted are similar to those of a Confidential clearance.

Legal

Prior to granting access to information, an individual who has been cleared must sign a Security Screening Certificate and Briefing Form (TBS/SCT 330-47), indicating their willingness to be bound by several Acts of Parliament during and after their appointment finishes. Anyone who has been given a security clearance and releases designated/classified information without legal authority is in breach of trust under section 18(2) of the Security of Information Act
Security of Information Act
In Canada, the Security of Information Act is part of the Canadian Anti-Terrorism Act which received Royal Assent on December 18, 2001 and came into effect on December 24, 2001. This Act renamed and replaced Official Secrets Act 1981...

with a punishment up to 2 years in jail. Those who have access to Special Operational Information are held at higher standards. The release of such information is punishable by law, under section 17(2) of the Security of Information Act
Security of Information Act
In Canada, the Security of Information Act is part of the Canadian Anti-Terrorism Act which received Royal Assent on December 18, 2001 and came into effect on December 24, 2001. This Act renamed and replaced Official Secrets Act 1981...

, liable to imprisonment for life.

The Criminal Code of Canada

Criminal Code of Canada

The Criminal Code or Code criminel is a law that codifies most criminal offences and procedures in Canada. Its official long title is "An Act respecting the criminal law"...

, Section 748 (3) states that no person convicted of an offence under Section 121 (frauds on the Government), Section 124 (selling or purchasing office), or Section 418 (selling defective stores to Her Majesty), has, after that conviction, the capacity to contract with Her Majesty or to receive any benefits under a contract between Her Majesty and any other person or to hold office under Her Majesty unless a pardon has been granted. (This effectively prohibits granting of a Reliability Status to any such individual.)

United Kingdom

Clearance is checked at four levels, depending on the classification of materials that can be accessed — Counter-Terrorist Check (CTC), Baseline Check (BC), Security Check (SC), and Developed Vetting (DV). Security Check allows an individual long-term unsupervised access to protectively-marked SECRET material, whilst for TOP SECRET Developed Vetting is required. All Officers and some specialist trades within the British Armed Forces are cleared to SC to enable them to carry out their jobs. Further to this, in the Royal Corps of Signals, all soldiers holding the appointment Foreman of Signals or Yeoman of Signals, and also certain appointments within the Intelligence Corps are DV cleared. Those with security clearance are commonly required to sign a statement to the effect that they agree to abide by the restrictions of the Official Secrets Act

Official Secrets Act

The Official Secrets Act is a stock short title used in the United Kingdom, Ireland, India and Malaysia and formerly in New Zealand for legislation that provides for the protection of state secrets and official information, mainly related to national security.-United Kingdom:*The Official Secrets...

. This is popularly referred to as "signing the Official Secrets Act". Signing this has no effect on which actions are legal, as the act is a law, not a contract, and individuals are bound by it whether or not they have signed it. Signing it is intended more as a reminder to the person that they are under such obligations. To this end, it is common to sign this statement both before and after a period of employment that involves access to secrets.

History

After America's entry into WWII, Britain changed its security classifications to match American classifications. Prior to the U.S.'s coming into the war, the classifications included the top classification: "Most Confidential". Documents were then shared with the U.S., when they entered the war. However, these British classifications were not understood in the U.S., and classified information appeared in the U.S. press. This spearheaded the uniformity in classification between the UK and the U.S.

Hierarchy

A security clearance is, in general, granted to a particular level of clearance. The exception to this is levels above compartmentalized access, when an individual is given access to a particular type of data. The President of the United States

President of the United States

The President of the United States of America is the head of state and head of government of the United States. The president leads the executive branch of the federal government and is the commander-in-chief of the United States Armed Forces....

must legally be given access to any government or military information he or she requests, even if he or she would not otherwise be able to obtain a security clearance were he or she not the President.

Controlled Unclassified Information

This is not a clearance, but rather a level at which information distribution is controlled. Controlled Unclassified is information that may be illegal to distribute. This information is available when needed by government employees such as Department of Defense (DoD) employees. It should not, however, be redistributed. An example of the type of information that may be controlled at this level is the operational details of a non-critical system.

Confidential

Also known as a "public trust" clearance, this is the simplest security clearance to get. This level typically requires a few weeks to a few months of investigation. A Confidential clearance requires a NACLC

National Agency Check with Local Agency Check and Credit Check

National Agency Check with Local Agency Check and Credit Check is a type of background check required in the United States for granting of security clearances....

investigation which dates back 7 years on the person's record and must be renewed (with another investigation) every 15 years. Applicants are required to complete federal Standard Form 85P

Secret

A Secret clearance, also known as Collateral Secret or Ordinary Secret, requires a few months to a year to fully investigate, depending on the individual's background. Some instances wherein individuals would take longer than normal to be investigated are many past residences, having residences in foreign countries, having relatives outside the United States, or significant ties with non-US citizens. Unpaid bills as well as criminal charges will more than likely disqualify an applicant for approval. However, a Bankruptcy will be evaluated on a case-by-case basis and is not an automatic disqualifier. Poor financial history is the number-one cause of rejection, and foreign activities and criminal record are also common causes for disqualification. A Secret clearance requires a NACLC, and a Credit investigation; it must also be re-investigated every 10 years. Investigative requirements for DoD clearances, which apply to most civilian contractor situations, are contained in the Personnel Security Program issuance known as DoD Regulation 5200-R, at part C3.4.2

Top Secret

Top Secret is a more stringent clearance. A Top Secret, or "TS", clearance, is often given as the result of a Single Scope Background Investigation

Single Scope Background Investigation

A Single Scope Background Investigation is a type of United States security clearance investigation required for Top Secret, SCI and Q access, and involves agents contacting employers, coworkers and other individuals...

, or SSBI. Top Secret clearances, in general, afford one access to data that affects national security

National security

National security is the requirement to maintain the survival of the state through the use of economic, diplomacy, power projection and political power. The concept developed mostly in the United States of America after World War II...

, counterterrorism/counterintelligence, or other highly sensitive data. There are far fewer individuals with TS clearances than Secret clearances. A TS clearance can take as few as 3–6 months to obtain, but more often takes 6–18 months, while sometimes taking up to 3 years to obtain. The SSBI must be renewed every 5 years. Also, in order to receive clearance, all initial TS candidates must pass an oral examination. This is conducted by a TS-cleared employee who has passed at least two SSBIs.

Compartmented Information

As with TS clearances, Sensitive Compartmented Information

Sensitive Compartmented Information

Sensitive compartmented information is a type of United States classified information concerning or derived from sensitive intelligence sources, methods, or analytical processes. All SCI must be handled within formal access control systems established by the Director of National Intelligence...

(SCI) clearances are assigned only after one has been through the rigors of a Single Scope Background Investigation

Single Scope Background Investigation

and a special adjudication process for evaluating the investigation. SCI access, however, is assigned only in "compartments." See Compartmentalization (intelligence)

Compartmentalization (intelligence)

In matters concerning information security, whether public or private sector, compartmentalization is the limiting of access to information to persons or other entities who have a need to know it in order to perform certain tasks....

. These compartments are necessarily separated from each other with respect to organization, so an individual with access to one compartment will not necessarily have access to another. Each compartment may include its own additional special requirements and clearance process. An individual may be granted access, or read into

Read into

The process of being read into a compartmented program generally entails being approved for access to particularly sensitive and restricted information about a classified program, receiving a briefing about the program, and formally acknowledging the...

to a compartment for an extended or only short period of time.

A representative list of kinds of information that may require compartmented access, without using specific national terminology, includes:

Cryptography
Cryptography
Cryptography is the practice and study of techniques for secure communication in the presence of third parties...
Overhead reconnaissance from aircraft, UAVs
Unmanned aerial vehicle
An unmanned aerial vehicle , also known as a unmanned aircraft system , remotely piloted aircraft or unmanned aircraft, is a machine which functions either by the remote control of a navigator or pilot or autonomously, that is, as a self-directing entity...

, or satellites IMINT
IMINT
Imagery Intelligence , is an intelligence gathering discipline which collects information via satellite and aerial photography. As a means of collecting intelligence, IMINT is a subset of intelligence collection management, which, in turn, is a subset of intelligence cycle management...
Communications intelligence, a subset of SIGINT
SIGINT
Signals intelligence is intelligence-gathering by interception of signals, whether between people , whether involving electronic signals not directly used in communication , or combinations of the two...
Design or stockpile information about nuclear weapons
Nuclear targeting.

Such compartmentalized clearances may be expressed as "John has a TS/SCI", whereby all clearance descriptors are spelled out verbally. For example, The US National Security Agency

National Security Agency

The National Security Agency/Central Security Service is a cryptologic intelligence agency of the United States Department of Defense responsible for the collection and analysis of foreign communications and foreign signals intelligence, as well as protecting U.S...

used to use specialized terms such as "Umbra", This classification is reported to be a compartment within the "Special Intelligence" compartment of SCI. The various NSA compartments have been simplified; all but the most sensitive compartments are marked "CCO", meaning "handle through COMINT channels only".

The US Department of Defense establishes, separately from intelligence compartments, special access programs (SAP) when vulnerability of specific information is exceptional and the normal criteria for determining eligibility for access applicable to information classified at the same level are not deemed sufficient to protect the information from unauthorized disclosure. The number of people cleared for access to such programs is typically kept low. Information about stealth technology

Stealth technology

Stealth technology also termed LO technology is a sub-discipline of military tactics and passive electronic countermeasures, which cover a range of techniques used with personnel, aircraft, ships, submarines, and missiles, to make them less visible to radar, infrared, sonar and other detection...

, for example, often requires such access.

Jobs that require a clearance

Anyone with access to classified data requires a clearance at or higher than the level at which the data is classified. For this reason, security clearances are required for a wide range of jobs, from senior management to janitorial. According to a 2010 Washington Post article, 854,000 Americans had top-secret clearances; almost one-third of them worked for private companies, rather than for the US Government.

Jobs that require a security clearance can be found either as positions working directly for the Federal government or as authorized Federal contractors. Over time, more clearance jobs are being outsourced to contractors. Due to an overall shortage in security-cleared candidates and a long time frame to obtain the credentials for an uncleared worker, those with clearance are often paid more than their non-cleared equivalent counterparts. According to one 2010 estimate, "people with security clearances are in the top 10 percent of wage earners in the country".

Requirements for a clearance

The vetting

Vetting

Vetting is a process of examination and evaluation, generally referring to performing a background check on someone before offering him or her employment, conferring an award, etc...

process for a security clearance is usually undertaken only when someone is hired or transferred into a position that requires access to classified information. The employee is typically fingerprint

Fingerprint

A fingerprint in its narrow sense is an impression left by the friction ridges of a human finger. In a wider use of the term, fingerprints are the traces of an impression from the friction ridges of any part of a human hand. A print from the foot can also leave an impression of friction ridges...

ed and asked to provide information about themselves. This becomes a starting point for an investigation into the candidate's suitability. The process has been streamlined and now requires the person who needs clearance to input the information online using E-qip

E-qip

e-QIP is a secure website managed by the United States Office of Personnel Management that is designed to automate the common security questionnaires used to process federal background investigations...

. 14 days are allowed, during which data must be input. Having the older paper form can be helpful for collecting and organizing the information in advance. The information on an investigation and its status is stored in either JPAS

E-qip

or Scattered Castles

E-qip

.

Investigative work is usually at least one of the following types:

National Agency Check with Local Agency Check and Credit Check
National Agency Check with Local Agency Check and Credit Check
National Agency Check with Local Agency Check and Credit Check is a type of background check required in the United States for granting of security clearances....

(NACLC). An NACLC is required for a Secret, L, and CONFIDENTIAL access. (See: Background check
Background check
A background check or background investigation is the process of looking up and compiling criminal records, commercial records and financial records of an individual....

)
Single Scope Background Investigation
Single Scope Background Investigation
A Single Scope Background Investigation is a type of United States security clearance investigation required for Top Secret, SCI and Q access, and involves agents contacting employers, coworkers and other individuals...

(SSBI). An SSBI is required for Top Secret, Q, and SCI access, and involves agents contacting employers, coworkers and other individuals. Standard elements include checks of employment; education; organization affiliations; local agencies; where the subject has lived, worked, or gone to school; and interviews with persons who know the individual. The investigation may include an NACLC on the candidate’s spouse or cohabitant and any immediate family members who are U.S. citizens other than by birth or who are not U.S. citizens.
Polygraph
Polygraph
A polygraph measures and records several physiological indices such as blood pressure, pulse, respiration, and skin conductivity while the subject is asked and answers a series of questions...

. Some agencies may require polygraph examinations. The most common examinations are Counter Intelligence (CI) and Full-Scope (Lifestyle) polygraphs. While a positive SSBI is sufficient for access to SCI-level information, polygraphs are routinely administered for "staff-like" access to particular agencies.

If issues of concern surface during any phase of security processing, coverage is expanded to resolve those issues. At lower levels, interim clearances may be issued to individuals who are presently under investigation, but who have passed some preliminary, automatic process. Such automatic processes include things such as credit checks, felony

Felony

A felony is a serious crime in the common law countries. The term originates from English common law where felonies were originally crimes which involved the confiscation of a convicted person's land and goods; other crimes were called misdemeanors...

checks, and so on. An interim clearance may be denied (although the final clearance may still be granted) for having a large amount of debt, having a foreign spouse, for having admitted to seeing a doctor for a mental health

Mental health

Mental health describes either a level of cognitive or emotional well-being or an absence of a mental disorder. From perspectives of the discipline of positive psychology or holism mental health may include an individual's ability to enjoy life and procure a balance between life activities and...

condition, or for having admitted to other items of security concern (such as a criminal record or a history of drug use.)

Investigations conducted by one federal agency are no longer supposed to be duplicated by another federal agency when those investigations are current within 5 years and meet the scope and standards for the level of clearance required. The high-level clearance process can be lengthy, sometimes taking a year or more. The long time needed for new appointees to be cleared has been cited as hindering U.S. presidential transitions.

Security briefings

In the U.S., once the clearance is granted, the candidate is briefed on "the proper safeguarding of classified information and on the criminal, civil, and administrative sanctions that may be imposed on an individual who fails to protect classified information from unauthorized disclosure." He or she is also required to sign an approved non-disclosure agreement

Non-disclosure agreement

A non-disclosure agreement , also known as a confidentiality agreement , confidential disclosure agreement , proprietary information agreement , or secrecy agreement, is a legal contract between at least two parties that outlines confidential material, knowledge, or information that the parties...

(e.g., form SF-312

Form SF-312

Standard Form 312 is a non-disclosure agreement required under Executive Order 13292 to be signed by employees of the U.S. Federal Government or one of its contractors when they are granted a security clearance for access to classified information...

). High level clearances are reviewed periodically and any "adverse information" reports received at any time can trigger a review. When a clear person leaves their job, they are often "debriefed" — reminded of their ongoing obligations to protect the information they were allowed to see.
According to NISPOM Chapter 3, newly cleared employees are required to receive an initial security briefing before having access to classified information. This training helps them understand the threat, risks to classified information, how to protect the classified information, security procedures and duties as they apply to their job. This training is followed up by refresher training that reinforces the initial security briefing.

Dual citizenship

Dual citizenship is associated with two categories of security concerns: foreign influence and foreign preference. Dual citizenship in itself is not the major problem in obtaining or retaining security clearance in the United States. If a security clearance applicant's dual citizenship is "based solely on parents' citizenship or birth in a foreign country", that can be a mitigating condition.
However, exercising (taking advantage of the entitlements of) a non-U.S. citizenship can cause problems. For example, possession and/or use of a foreign passport

Passport

A passport is a document, issued by a national government, which certifies, for the purpose of international travel, the identity and nationality of its holder. The elements of identity are name, date of birth, sex, and place of birth....

is a condition disqualifying from security clearance and "... is not mitigated by reasons of personal convenience, safety, requirements of foreign law, or the identity of the foreign country" as is explicitly clarified in a Department of Defense policy memorandum which defines a guideline requiring that "... any clearance be denied or revoked unless the applicant surrenders the foreign passport or obtains official permission for its use from the appropriate agency of the United States Government".
This guideline has been followed in administrative rulings by the United States Department of Defense

United States Department of Defense

The United States Department of Defense is the U.S...

(DoD) Defense Office of Hearings and Appeals (DOHA) office of Industrial Security Clearance Review (ISCR), which decides cases involving security clearances for Contractor personnel doing classified work for all DoD components. In one such case, an administrative judge ruled that it is not clearly consistent with U.S. national interest to grant a request for a security clearance to an applicant who was a dual national of the U.S. and Ireland.

Individuals who have had security clearances revoked

In the post World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

era there have been several highly publicized, and often controversial, cases of officials or scientists having their security clearances revoked, including:

Sandy Berger
Sandy Berger
Samuel Richard "Sandy" Berger was United States National Security Advisor, under President Bill Clinton from 1997 to 2001. In his position, he helped to formulate the foreign policy of the Clinton Administration...
John M. Deutch
John M. Deutch
John Mark Deutch is an American chemist and civil servant. He was the United States Deputy Secretary of Defense from 1994 to 1995 and Director of Central Intelligence from May 10, 1995 until December 15, 1996...
Abdel-Moniem El-Ganayni
Abdel-Moniem El-Ganayni
Dr. Abdel-Moniem ibn Ali El-Ganayni is an Egyptian-born American nuclear physicist, former prison Imam, and an active member of the Pittsburgh Muslim community. In 2007 El-Ganayni's U.S...
Wen Ho Lee
Wen Ho Lee
Dr. Wen Ho Lee is a Taiwan-born Taiwanese American scientist who worked for the University of California at the Los Alamos National Laboratory. He created simulations of nuclear explosions for the purposes of scientific inquiry, as well as for improving the safety and reliability of the US nuclear...
Robert Oppenheimer
Robert Oppenheimer
Julius Robert Oppenheimer was an American theoretical physicist and professor of physics at the University of California, Berkeley. Along with Enrico Fermi, he is often called the "father of the atomic bomb" for his role in the Manhattan Project, the World War II project that developed the first...
Alan Turing
Alan Turing
Alan Mathison Turing, OBE, FRS , was an English mathematician, logician, cryptanalyst, and computer scientist. He was highly influential in the development of computer science, providing a formalisation of the concepts of "algorithm" and "computation" with the Turing machine, which played a...

(UK)
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

Canada

Background

Security screening

Security assessment/clearances

Site access

Legal

United Kingdom

History

Hierarchy

Controlled Unclassified Information

Confidential

Secret

Top Secret

Compartmented Information

Jobs that require a clearance

Requirements for a clearance

Security briefings

Dual citizenship

Individuals who have had security clearances revoked

See also

Canada

UK

US