The use of the Boeing TEA-230 Subsonic Flow Analysis method as a primary design tool in the development of cruise overwing nacelle configurations is presented. Surface pressure characteristics at 0.7 Mach number were determined by the TEA-230 method for a selected overwing flow-through nacelle configuration. Results of this analysis show excellent overall agreement with corresponding wind tunnel data. Effects of the presence of the nacelle on the wing pressure field were predicted accurately by the theoretical method. Evidence is provided that differences between theoretical and experimental pressure distributions in the present study would not result in significant discrepancies in the nacelle lines or nacelle drag estimates.