David is the Technical Publishing Manager at 4D Technologies, where he develops the CADLearning courses and eBooks for AutoCAD and other Autodesk products. He has more than 25 years of hands-on experience with AutoCAD and more than 12 years with Revit as a user, developer, author and consultant and is both an AutoCAD and Revit Certified Professional. A contributing editor to Desktop Engineering magazine, he is also the former senior editor of CADalyst magazine, and the author of more than a dozen books about AutoCAD. A licensed architect, David was also one of the earliest AutoCAD third-party software developers, creating numerous AutoCAD add-on programs. As an industry consultant, David has worked with many companies, including Autodesk. He has taught college-level AutoCAD courses and has consistently been a top-rated speaker at Autodesk University.