A wind tunnel experiment exploring the influence of interface geometry on wing-body aerodynamics is described and the results are presented. The investigation focuses on the interference effects that occur for several wing-body geometries that are considered candidates for a design of an airplane intended to operate at low subsonic speeds at high altitude. The geometries of the test models were developed by Aurora Flight Sciences as in the process of evolving a preliminary design for a potential future unmanned aerial vehicle. With the support of the Glenn L. Martin Wind Tunnel at the University of Maryland, an experimental program has been carried out in which force data were obtained to identify the most promising wing-fuselage geometries for future detailed development. The research also included computational fluid dynamics simulations to explore flow characteristics around these wing-fuselage systems in greater detail than was possible in the experiments. The experimental data and simulation results are discussed in this thesis.