A design approach based on diverse pinch point and mathematical programming for optimal integration of heat exchanger networks (HENs) is described. The effect of the dissimilar film heat transfer coefficients on the area target is considered by different pinch and composite curves. The approach combines insightful pinch analysis and rigorous mathematical programming, which enable systematic and automatic designs. A software platform is developed for the design of HENs. An example illustrates the application of the proposed approach.