There are many areas of Mechanical Engineering more diverse and powerful and one of the area is Mechanical Drawing with a broader and richer history. From history, root has been traced from design sketches, complicated to understand, of Leonardo–di–Vinci to the cave of ancient humans in form of paintings, as simple as child's sketch, on cave's wall. From fundamental questions of Mechanical Engineering drawing to the drawing the assembly and disassembly, the Mechanical Engineering drawing remains at the forefront of today's teaching. At the same time, new innovative applications such as use of latest software appear everywhere around us. To present to a student such a wonderful, multifaceted, mental jewel in a way that maintains the excitement while not compromising elegance and rigor, is a challenge no teacher can resist. It is not too difficult at the undergraduate level where, in a series of courses, the student sees that the simple solutions for development of surfaces, intersection of solids and the entire standard used in preparing the assembly and disassembly of the mechanical component. This book has evolved from over 25 years of teaching advanced seniors and graduate students a core course on the application of the full–range field theory of Mechanical drawing. It is presented to help teachers meet the challenges of leading students in their exciting discovery of the unifying field theories of assembly of the mechanical components. The intention is to concentrate on fundamental concepts, basic applications, simple problems, steps to solve the problems and unanswered questions. This book, therefore, becomes quite different from other texts covering essentially the same subject matter at this level. First, by including more number of solved problems in different category of development of surfaces and intersection of solid as well as the basic concepts preparation before starting the assembly drawing of the mechanical components. I have found that students are facing the difficulty in solving the problems of assembly due to lack of understanding of the assemble parts in the systematic way fittings to understand the basic concepts of fitting. Secondly, while the theory presented in the first three chapters covers familiar ground, the emphasis in its development and intersection of solids.