This paper presents an analysis of the requirement to be able to exchange or share data about assembly mating conditions between different computer systems. The challenge is that although drawing and solid model data can be exchanged between different systems, there are currently no methods of exchanging data about assembly mating conditions. A brief assessment of existing data exchange technologies is presented, the benefits of a canonical representation for mating conditions are discussed, and some of the information requirements that need to be satisfied are detailed. The requirement for a canonical representation is illustrated with a data model that satisfies the information requirements. An example of the use of the data model to describe a mating condition is presented
