Inherited disorders of purine and pyrimidine metabolism in man lead to severe diseases. At the 2nd M}nchner Adventssymposium the state of the art as to the genetic basis, clinical aspects, and the biochemical basis has been given by leading experts in the fields concerning the following diseases: Hypoxanthine phosphoribosyltransferase deficiency (HGPRT-deficieny), adenine phosphoribosyltransferase deficiency (APRT-deficiency), hyperuricemia and gout, adenosine deaminase deficiency (ADA-deficiency, purine nucleoside phosphorylase deficiency (PNP-deficiency). All contributions of the symposium are published within this volume thus giving and overview of this most interesting field.