This Standard describes a data model to support the interchange of data elements and their values between a content object and a runtime service (RTS). It is based on a current industry practice called - computer managed instruction - (CMI). The work on which this Standard is based was developed to support a client/server environment in which a learning technology system, generically called a learning management system (LMS), delivers digital content, called content objects, to learners. The data model supports learner data and preferences, interactions, objectives, content-object entry, exit, and status information, time parameters, and scores.