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See the WHAT'S NEW IN AUTOCAD MEP 2012 video from Autodesk here.
AutoCAD MEP design and construction documentation software is built for mechanical, electrical, and plumbing (MEP) engineers, designers, and drafters. Seamlessly collaborate with architects using AutoCAD Architecture software in an intuitive design environment. Minimize coordination errors between mechanical, electrical, and plumbing engineering design teams as well as with architects and structural engineers.