The Canadian Trade-Document Alignment System (CTDAS) layout key and master establish the basis for the standardization of forms used within Canadian domestic and international trade.

This standard specifies the format and dimensions of the CTDAS layout key. It shows the application of the CTDAS layout key to the CTDAS master, from which further documents in the system are generated.

This standard covers the data fields on the master, identifying their locations and outlining the nature of the data to be entered. It also identifies those areas of the master that are optional, depending upon the requirements of the aligned series of forms.

The CTDAS is in conformity with an internationally recognized trade-information system based on the "United Nations Layout Key for Trade Documents" developed by the United Nations Economic Commission for Europe, a precise layout for forms used in trade.