In the tradition of its predecessor, the main purpose of this volume is the dissemination of statistical methodologies in the area of biological and medical sciences. The chapters are written by specialists with considerable experience in the application of statistical techniques for investigating biological issues. The volume is divided into four parts and the chapters illustrate some recent work on many issues. Most of the papers discuss the statistical principles in conjunction with specific applications. As a result biological as well as statistical readers will benefit from this exposition, and obtain the current state of knowledge in these areas. Many authors emphasize the open problems that might lead to further work on these subjects.