The book is the first in the domestic science of labor law to study the possibility of the existence of plurality of persons on the employer’s side and the main problems of legal regulation arising in connection with this phenomenon. The author analyzes the possible forms of plurality of persons in private law and labor law relations and their impact on the conclusion , implementation and termination of the employment contract, as well as the financial liability of the employer. The publication is intended for students and graduate students of law schools, researchers and practitioners specializing in the field of labor or civil law.