A recently developed second-moment Reynolds stress model was applied to two challenging high-lift flows: (1) transonic flow over the ONERA M6 wing, and (2) subsonic flow over the DLR-F11 wing-body configuration from the second AIAA High Lift Prediction Workshop. In this study, the Reynolds stress model results were contrasted with those obtained from one-and two-equation turbulence models, and were found to be competitive in terms of the prediction of shock location and separation. For an ONERA M6 case, results from multiple codes, grids, and models were compared, with the Reynolds stress model tending to yield a slightly smaller shock-induced separation bubble near the wing tip than the simpler models, but all models were fairly close to the limited experimental surface pressure data. For a series of high-lift DLR-F11 cases, the range of results was more limited, but there was indication that the Reynolds stress model yielded less-separated results than the one-equation model near maximum lift. These less-separated results were similar to results from the one-equation model with a quadratic constitutive relation. Additional computations need to be performed before a more definitive assessment of the Reynolds stress model can be made. Nomenclature a speed of sound, m/s A wing reference area, m 2 AR wing aspect ratio b wing reference span, m c ref wing reference chord, mcomponent of diffusion tensor, m 2 /s 3 d distance to the nearest wall, m F 1 Menter's blending function F T fully turbulent g alternate scale-determining variable, 1/ω, s 1/2 k specific kinetic turbulence energy, m 2 /s 2 M ∞ freestream Mach number O ij normalized rotation tensor used in quadratic constitutive relation correction P two-equation model production term, τ ij (∂û i /∂x j ), kg/(ms 3 ) P ij Cartesian component of Reynolds-stress production tensor, m 2 /s 3 * Research Engineer, Computational AeroSciences Branch, E.Lee-Rausch@nasa.gov. Associate Fellow AIAA.