This paper describes the control law for engaging and disengaging a dry clutch used for connecting an engine to a drivetrain in a Parallel Hybrid Electric Vehicle (PHEV). Brief descriptions of the component models and subsytem controllers are presented along with the powertrain’s dynamic equations. The engine clutch control is described in detail, including engagement and disengagement simulations. The hybrid drivetrain, (Figure 1), includes a conventional 2.01 spark-ignited, internal combustion engine and an dry clutch attached directly to an engine flywheel. The output of the dry clutch is connected to a starter/alternator (S/A) that starts the engine, charges and discharges a high-powered energy storage device and provides additional motive power. The powertrain is completed by a converterless automatic transmission connected to a differential and halfshafts that drive the front wheels. The engine clutch control strategy is presented together with simulations that demonstrate system performance.