Device-to-device (D2D) communication is expected to play a significant role in the fifth-generation (5G) networks. To support seamless mobility and service continuity, the device(s) undergoing D2D communication should be handed over to the best access network among all the available wireless access networks. A seamless vertical handover (VHO) across the heterogeneous wireless networks is the key enabling solution for achieving the seamless service continuity and mobility. The VHO algorithm should be intelligent, and the decisions should also consider the quality requirements other than the conventional received signal strength (RSS). In this work, a two-stage fuzzy-logic-based VHO decision algorithm is developed to select suitable access network based on the quality-of-service requirements. The quality parameters like data rate and latency are given as the fuzzy inputs along with RSS. The resource availability check is also carried out for the target network, which makes the decision more intelligent. The simulation results show that the proposed scheme offers better performance than the traditional multi-attribute decision-making schemes. © 2018, King Fahd University of Petroleum & Minerals.