Future generation wireless networks will demand more intelligent and adaptive handover decision mechanisms to fulfill users' expectations in terms of seamless mobility over extensive area, minimum price, high data rate, adequate QoS provision and so on. For such a demanding networking environment the Handover Decision System (HDS) need to be highly intelligent. Fuzzy logic appears to be one of the methods that can be employed to enhance HDS intelligence. However, most existing fuzzy-based HDS designs proposed in the literature are monolithic, i.e. based on a single fuzzy engine.