Automatically adding constraints between entities in a subject computer-aided design (CAD) model of a real-world object includes storing information regarding CAD model entities and related constraints in a computer database in which the CAD model entities belong to one or more components of the subject CAD model or other CAD models. The computer database is accessed to determine previously used constraints for at least one entity of a given component being added to the CAD model, and constraints are automatically added between at least one entity of the given component and another entity in the subject CAD model based on the previously used constraints.