The previous volumes in this series on soft tissue sarcomas highlighted the importance of the multidisciplinary approach to treatment, and this focus is continued in the present volume. Proper diagnosis and staging remain the cornerstone of the treatment strategy. Sophisticated histopathology tech niques and growing consensus on grading systems have further increased the importance of the histopathologist in providing estimates of patient prognosis as well as in providing data for planning the treatment strategy. The use of cytogenetics in this field is rapidly increasing and might enable the distinction of subgroups in specific histological tumor types. Furthermore, molecular biological studies not only help reveal inherited predispositions and details in tumor oncogenesis, but they may also provide additional predictive factors for tumor behavior. Further data on treatment strategy will be provided by diag nostic imaging, and in this volume the value of PET imaging, a relatively new achievement, is highlighted. As far as the actual treatment is concerned, surgery still provides the major opportunity for cure. The addition of radiotherapy to surgery is of utmost importance in efforts to spare as much tissue as possible. The chapters on the planning of radiotherapy, brachytherapy, and the treatment of benign soft tissue lesions using radiotherapy are new contributions to this book. One of the potential late problems of radiotherapy is the occurrence of secondary soft tissue sarcomas, which is discussed in Chapter 10.