Developers
The ESRI Mapping Specification for Drawings [pdf] is a data standard for encoding ArcGIS information within a DWG file. It is a structured framework designed to enable software developers to build AutoCAD applications that interoperate with ArcGIS data more efficiently.
The Mapping Specification for Drawings uses standard AutoCAD Xrecords and object dictionaries to store a GIS coordinate system, feature class schema, and feature attributes directly to AutoCAD entities. It can be implemented using AutoLISP™, Visual Lisp™, and the ObjectARX™ programming environment in C# .NET, VB .NET, C++ and the OpenDWG® toolkit.
The SDK includes sample code in:
GIS and CAD Professionals
An AutoCAD application implementing this specification allows AutoCAD users to work directly with geodatabase information and configure GIS content for use with AutoCAD layers, line styles, color etc. This enables users to integrate CAD drawings and ArcGIS, and can be particularly useful in mixed GIS and CAD workflows.