Standard Data Models A standard data model13 or Industry Standard Data Model (ISDM) is a data model that is widely applied in some industry, and shared amongst competitors to some degree. There are a number of standard data models, defined by industry bodies, vendors, and others. Many use ERA modeling notations to describe relational structures. Others take the form of hierarchical vocabularies. A particularly extensive standard data model is the US National Information Exchange Model™ (NIEM™).14 The NIEM model includes core elements and elements specific to particular communities.