Unity and Diversity offers a comprehensive overview of psychiatric diagnosis and nosology. Specially commissioned chapters by leading experts representing twenty different developing and developed Western and Eastern countries cover historical roots, recent developments, and current issues. The chapters are organized into five sections. The first reviews international and representative national diagnostic systems; the second, specific syndromes; the third, nomenclature and assessment; the fourth, nosology; and the fifth, the prospects of the upcoming Tenth Revision of the International Classification of Diseases. Seventy-five percent of the psychiatrically disordered population live in the Third World, and the need for a more truly international science of psychiatry is great. This volume helps to meet that need. It will be an indispensable reference for all mental health researchers and professionals.