An improvement to boundary layer control system, including a transpiration panel (58) for transpiring suction air in a distributed manner, is provided. The transpiration panel (58) replaces the discharge nozzle of prior art flow control systems. The transpiration panel (58) is generally a rigid panel having a plurality of small holes (62) extending from an inner panel surface (56) to a smooth outer panel surface (54). The transpiration panel (58) is positioned flush with an external aircraft surface in a region where laminar flow control is not being attempted. Exemplary subsonic and supersonic boundary layer control systems including the transpiration panel (58) are provided. A preferred location of the transpiration panel (58) for the subsonic application is the underside of a wing (80), near the leading edge. A preferred location of the transpiration panel (58) for the supersonic application including on the upper surface of a wing (114) near the fuselage (118), in a turbulent wedge region.