This book is a guide to the training of experts and breeders who conduct breeding work with breeds. The book includes a program of expert courses and covers all its sections. Test questions are included in the exam papers. The main sections of the book are devoted to the exterior of dogs and its assessment, organization of exhibitions, breeding work with breeds, breeding and education of our four-legged friends. Issues of dog anatomy and physiology, genetics and the laws of heredity are covered in an intelligible form, with a purely practical bias. With great completeness, the authors present the history of the domestication of dogs, their role in the development of humanity and the path of development of cynology in our country. The book was originally conceived as a manual for dog breeders taking courses for expert cynologists. But the practical experience of the authors, presented warmly and vividly, will undoubtedly interest both a novice dog breeder and a highly experienced expert. Authors: Gusev Vladimir Gavrilovich - expert of the All-Union category in all breeds of dogs, Guseva Elena Sergeevna - expert of the All-Russian category in hunting dog breeding.