High fuel costs, stringent safety and pollution standards and the need to increase plant life-time have all driven the search for better boiler control. Traditional PID control cannot achieve the best possible results as it does not account for the strong interactions between the controlled variables. Much work has been done in the area of optimal control, but the improvements gained in performance have been lost to some extent by the difficulties involved in tuning such controllers. A linear predictive controller is presented in this paper, which is both fully multivariable and computationally efficient. It is also easy to tune as the controller tuning parameters are physically meaningful.