The present volume contains papers developed from courses given at the International Union of Forest Research Organizations (IUFRO) Bio chemical Genetics Workshop (Working Party S.04-5) held at the Univer sity of Gottingen, Germany on July 5 through 28, 1973. The workshop was organized by Professor Robert G. Stanley and was held in memory of Professor Klaus Stern. Unfortunately, both met with untimely deaths. Professor Stanley was also instrumental in initiating the process of having the workshop proceedings published. I was asked by the workshop participants to complete this task, and I wish to acknowledge their cooperation, advice and encouragement. In addition to the courses and subsequent papers resulting from the above workshop, we have included some papers by colleagues who were unable to attend the meeting. The contents of this text may, there fore, be considered a working-manual of generally "modern" techniques that are applicable to forest genetics and breeding programs. The chapters are placed in five major categories. The first three categories follow according to classes of chemical constituents in herent to plants which are nucleic acids (DNA, RNA) , primary gene products (amino acids, proteins and enzymes) and primary and secon dary metabolites (carbohydrate polymers, resins, phenolics, pigments, etc.). The fourth category is concerned with the interaction of en vironment and gene systems. Indirect selection, crossing and proto plasmic and flowering manipulation are factors covered in the fifth category.