The subject of evaporator control has been investigated and some recent developments have been presented. Three levels of control are proposed :juice flow control, syrup brix control, and the optimal distribution of juice to the three first effects. Good juice flow control is crucial not only to improved evaporator control, but also to good clarification and pH control .a novel algorithm has been presented, and its advantages have been discussed briefly. Syrup brix is significantly affected by a number of factors, and these are efficiently incorporated into an MPC framework. This type of control also allows input and output constraints to be accommodated. Finally ,there is an optimal distribution of clear juice to the first effect vessels, which may be determined by their observed heat transfer coefficients.