Within the last 10-13 years Binary Decision Diagrams (BDDs) have become the state-of-the-art data structure in VLSI CAD for representation and manipulation of Boolean functions. Today, BDDs are widely used and in the meantime have also been integrated in commercial tools, especially in the area of verification and synthesis. The interest in BDDs results from the fact that the data structure is generally accepted as providing a good compromise between conciseness of representation and efficiency of manipulation. With increasing numbers of applications, also in non-CAD areas, classical methods of handling BDDs are being improved and new questions and problems evolve and have to be solved. Binary Decision Diagrams: Theory and Implementation is intended both for newcomers to BDDs and for researchers and practitioners who need to implement them. Apart from giving a quick start for the reader who is not familiar with BDDs (or DDs in general), it also discusses several new aspects of BDDs, e.g. with respect to minimization and implementation of a package. It is an essential bookshelf item for any CAD designer or researcher working with BDDs.