A collection of software tools are presented which provide a programming interface for macromolecular Crystallographic Information File (mmCIF) dictionaries and data files. These tools are part of a software framework developed by the Nucleic Acid Database (NDB) [1, 2] to address practical problems encountered in processing and validating data in mmCIF format. This software framework includes both relational and object oriented programming interfaces to mmCIF as well as a simple set of tools which facilitate the exchange of mmCIF data. In addition to the description of the architectures of the programming interfaces and software tools, this tutorial will provide practical applications of each programming interface and will focus on how these tools may be used to integrate of mmCIF data into new and existing applications. Participants are encouraged to bring application programs for which they wish to construct an mmCIF interface.