An operator-assisted call is one in which the calling party

Calling party

The calling party is a person who initiates a telephone call over the public switched telephone network, usually by dialing a telephone number....

 places a telephone call

Telephone call

A telephone call is a connection over a telephone network between the calling party and the called party.-Information transmission:A telephone call may carry ordinary voice transmission using a telephone, data transmission when the calling party and called party are using modems, or facsimile...

 which requires an operator

Telephone operator

A telephone operator is either* a person who provides assistance to a telephone caller, usually in the placing of operator assisted telephone calls such as calls from a pay phone, collect calls , calls which are billed to a credit card, station-to-station and person-to-person calls, and certain...

 to provide some form of assistance in completing the call. This may include telephone

Telephone

The telephone , colloquially referred to as a phone, is a telecommunications device that transmits and receives sounds, usually the human voice. Telephones are a point-to-point communication system whose most basic function is to allow two people separated by large distances to talk to each other...

 calls made from pay phones, calls placed station-to-station, person-to-person, collect

Collect call

A collect call in the USA and Canada or reverse charge call in the UK and other countries is a telephone call in which the calling party wants to place a call at the called party's expense...

, third number call

Third number call

A third number call or third party call is an operator assisted telephone call that can be billed to the party other than the calling and called party.The operator calls the third number for the party to accept the charges before the call can proceed....

s, calls billed to a credit card

Credit card

A credit card is a small plastic card issued to users as a system of payment. It allows its holder to buy goods and services based on the holder's promise to pay for these goods and services...

, and certain international call

International call

International telephone calls are those made between different countries. These telephone calls are processed by international gateway exchanges . Charges for these calls were high initially but declined greatly during the 20th century due to advances in technology and liberalization. Originally...

s which cannot be dialed directly.

Before the advent of emergency telephone number

Emergency telephone number

Many countries' public telephone networks have a single emergency telephone number, sometimes known as the universal emergency telephone number or occasionally the emergency services number, that allows a caller to contact local emergency services for assistance. The emergency telephone number may...

s, operators identified and connected emergency calls to the correct emergency service

Emergency service

Emergency services are organizations which ensure public safety and health by addressing different emergencies. Some agencies exist solely for addressing certain types of emergencies whilst others deal with ad hoc emergencies as part of their normal responsibilities...

. Directory assistance

Directory assistance

In telecommunications, directory assistance or directory enquiries is a phone service used to find out a specific telephone number and/or address of a residence, business, or government entity.-Technology:...

 was also part of the operator's job.

Operator-assisted calls can be more expensive than direct dial calls.

A person-to-person call is an operator-assisted call in which the calling party wants to speak to a specific party and not simply to anyone who answers. The caller is not charged for the call unless the requested party can be reached. This method was popular when telephone calls were relatively expensive.

An operator-assisted conference call or op assist call is one in which the conference call is managed by an operator. The telephone operator will greet each calling participant, gather specific information from each calling participant, introduce key speakers, and manage questions and answers all from the telephone.

Station-to-station is a method of placing a telephone call, with or without assistance, in which the calling party

Calling party

The calling party is a person who initiates a telephone call over the public switched telephone network, usually by dialing a telephone number....

 agrees to talk to whoever answers the telephone. With the introduction of direct dial telephone service and the subsequent drop in the price of long distance telephone calls, person-to-person service is virtually unheard of. Fax machines and modems, due to their inability to ask for a party by name, use the station-to-station technique.

List of operator assistance numbers

• North America
  • 0 – operator assistance (local)
  • 00 - operator assistance (long distance provider;after AT&T breakup)
• Asia
  • 10010 – local operator assistance in Hong Kong
  • 10013 – international operator assistance in Hong Kong
• United Kingdom
  • 100 – operator assistance.