As group therapy nears its 100th anniversary and as we simultaneously approach the next century, this author team looks back on the past and present developments and identifies future trends.The emphasis of this text is to understand the advances which have taken place in group treatment over the years, regardless of what historical events created or influenced them, and to focus on what the clinical and research data has identified as reputable and beneficial forms of group psychotherapy. As the book's title implies, the primary concern is pragmatic and is geared to students and practitioners of group therapy who whish to advance their existing base of knowledge and to enhance and broaden their leadership skills. In order to accomplish this goal, the text is designed to provide a brief historical context against which one can compare and contrast contemporary group methods and identify long-standing trends in the group field. This will be followed by an overview of the basic principles of group treatment with specific reference to leadership and membership issues involved in clinical decision making and choice of group interventions selected. The focus in the latter part of the text will be on the newer uses of group and an in-depth discussion of the theory, structure, and practice of these innovative group formats. Selected forms of group therapy which are unique, underemphasized in the group literature, and which demonstrate creative adaptation of traditional group theory and technique will form the focal points for this section. The text concludes with some speculation about groups of the future and about further applications of group treatment to meet the needs of people in arapidly changing world.