Joao Santos is the manager and main instructor at QualiCAD (www.qualicad.com), one of the most important Portuguese ATCs (Autodesk Authorized Training Center),based in Lisbon. With a degree in Mechanical Engineering,he has been teaching AutoCAD for more than 25 years and,most recently teaching several AutoCAD clones such as DraftSight, ZW CAD, ProgeCAD,BitCAD.He is an AutoCAD 2013 and 3ds Max 2013 Certified professional user and instructor,being also the Portuguese instructor in these technologies with more students.João is the author and co-author of more than 40 Portuguese AutoCAD and 3ds Max books.He is also the author of Autodesk AutoCAD 2013 Practical 3D Drafting and Design,Packt Publishing.