Current environmental problems such as formation of smog and ozone in cities mainly originate from emissions of hydrocarbons released by the transportation sector. Therefore authorities have, mainly in the USA and the EU, mandated both lower exhaust emission standards and more stringent evaporative emission test procedures for vehicles. In order to reduce the evaporative emissions from the fuel tank, most modern cars use an evaporative emission management system. However, without careful control of the system, exhaust emissions can increase. Here a control method is presented for an evaporative emissions management system. The control method is based on a model of a spark-ignited (SI) engine and a model of an evaporative emissions management system. Included in the control method are estimations of the vapour flow and composition of air and fuel in the vapour from the evaporative emissions management system. The estimates are thereafter used in an improved fuel control algorithm in order to reduce the exhaust emissions. The improved fuel control algorithm is simulated and validated together with a model of an SI-engine. Simulations show that the control method presented might substantially improve the exhaust emissions control. A closer study of the carbon canister, a part of the evaporative emissions management system, is also presented.