This text reviews all conversion processes. The reaction mechanisms, the operating conditions and the advantages and disadvantages of each process are carefully analyzed and summarized. Refining flow sheets involving several conversion processes are studied. Concrete results are given and commented upon. The book is designed to help refiners to make technical and economic choices among different processes so as to develop the refining flowsheet that best suits their needs.Contents: I. Processing routes with carbon rejection. General. 1. Physical processes with carbon rejection. 2. Carbon rejecting processes by thermal treatment. II. Resid process without carbon rejection. General. 1. Thermal conversion processes. 2. Catalytic conversion under hydrogen pressure. 3. Resid processing schemes. References.