AutoCAD Civil 3D

[#1]

What is the diference?

[#2]

Completely different products. Both do CE type work, but you're comparing Mechanical Desktop and Inventor. http://usa.autodesk.com/adsk/servlet/index?siteID=123112&id=3566722 http://usa.autodesk.com/adsk/servlet/index?siteID=123112&id=3096064 On a side note, you should call your reseller. Their job is to explain all of these things to you and make sure you get the best product for your work. While C3D can't actually be bought currently, at some point it will be available. -- James Wedding, P.E. IT Manager Jones & Boyd, Inc. Dallas, TX XP/1 on P4-1.6/512 LDT2004+C3D