The main objective of this book is to introduce the subject ?Process Planning and Cost Estimation? in an integrated manner to the students of Mechanical Engineering and Production Engineering classes. Process Planning, Cost Estimation and Costing are the critical factors for the continued success of manufacturing enterprises. The world is an international market place. For a manufacturing company to be competitive in the international market place, process planning must be logical, rational, economical; and costs of products, sub-assemblies and components must be accurately estimated; in order to secure business, its costing must also be accurate to correctly determine the profitability of the various products manufactured. Our engineering students are required to learn these concepts in the early stages of their professional career so that" they become aware of the cost implications of any decision: engineering, technology or management, they take. It is essential that Mechanical Engineers and Production Engineers play a leading role in the determination of cost estimates and that they work with professional Cost Accountants to obtain realistic cost estimates. This book is an attempt towards this direction.