Semantic integrity constraints are business-specific rules that limit the permissible values in a database. For example, a university rule dictating that an "incomplete" grade cannot be changed to an A constrains the possible states of the database. To maintain database integrity, business rules should be identified in the course of database design and must be enforced during database implementation. Unfortunately, the manner by which current database management systems (DBMS) support the specification and enforcement of semantic integrity constraints varies considerably. This paper categorizes semantic integrity constraints and presents a simple approach for teaching users how to implement each of the five categories in Microsoft Access. (Contains 1 table and 4 figures.)