Data model patterns are reusable modeling structures that can be applied to a wide class of situations. There are elementary, assembly, and integration data model patterns. Elementary patterns are the ‘nuts and bolts’ of data modeling. They include ways to resolve many-to-many relationships, and to construct self-referencing hierarchies. Assembly patterns are often published and can give the modeler proven, robust, extensible, and implementable designs. Integration patterns provide the framework for linking the assembly patterns in common ways.