Method for reducing exhaust emission of an engine system

The method involves assisting the internal combustion engine (3) with the starter motor (4) until the operating temperature of the exhaust gas treatment device (1) is reached. The power output of the starter motor is regulated so that existing and/or forthcoming power requirements of the drive system and/or of auxiliary devices are fulfilled by the starter motor. AN Independent claim is also included for the following: (a) an engine system with an internal combustion engine, starter motor and exhaust gas treatment device.