The A.M. Isayev Chemical Engineering Design Bureau (Russian: Конструкторское бюро химического машиностроения имени A.M. Исаева), also known as KB KhIMMASH, is a Russian rocket engine design and manufacturing company. It is located in the city of Korolyov, Moscow Oblast. It started as the OKB-2 division of the NII-88 research institute, where Isayev directed the development of liquid rocket engines for ballistic submarines.