An Engineering Change Notice (ECN), or Change Notice, is a document which records or authorises a change to a design. The reasons for the change should also be recorded.

Following sound engineering

Engineering

Engineering is the discipline, art, skill and profession of acquiring and applying scientific, mathematical, economic, social, and practical knowledge, in order to design and build structures, machines, devices, systems, materials and processes that safely realize improvements to the lives of...

 principles, control and documention are necessary to ensure that changes are built upon a known foundation and approved by relevant authorities.

"[A] document approved by the design activity that describes and authorizes the implementation of an engineering change to the product and its approved configuration documentation".

An ECN must contain at least this information:

• Identification of what needs to be changed. This should include the part number and name of the component and reference to the drawings that show the component in detail or assembly.
• Reason(s) for the change.
• Description of the change. This includes a drawing of the component before and after the change. Generally, these drawings are only of the detail affected by the change.
• List of documents and departments affected by the change. The most important part of making a change is to see that all pertinent groups are notified and all documents updated.
• Approval of the change. As with the detail and assembly drawings, the changes must be approved by management.
• Instruction about when to introduce the change—immediately (scrapping current inventory), during the next production run, or at some other milestone.

See also

• Change management (engineering)
• Change control
  Change Control
  Change control within Quality management systems and Information Technology systems is a formal process used to ensure that changes to a product or system are introduced in a controlled and coordinated manner...
  
  
• Change request
  Change request
  A change request is a document containing a call for an adjustment of a system; it is of great importance in the change management process. A change request is not raised for a wording change in a letter....
  
  
• Engineering Change Order
  Engineering Change Order
  Engineering Change Orders are used for changes in components, assemblies, or documents such as processes and work instructions. They may also be used for changes in specifications....