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Langmuir circulation (LC) and wave breaking are turbulent processes driven by wind and surface waves that are critical in mixing of the ocean surface layer. The effects of LC and breaking waves on upper ocean turbulence are poorly understood, partly because of their mutual entanglement and their interactions with turbulence generated by shear and buoyancy. Utilizing turbulence measurements and a numerical model, we undertake a systematic comparison between observations and simulations of the wave-influenced surface boundary layer. Data sets obtained from the Surface Waves Process Program, the Coastal Mixing and Optics Experiment, and the Coupled Boundary Layers and Air-Sea Transfer experiment provide unique turbulence observations for a wide range of sea and wind conditions. The numerical model is based on a novel large eddy simulation (LES) that incorporates turbulent processes due to LC, buoyancy, shear, and breaking waves, while satisfying the conservation of momentum and energy. Research objectives include quantitative estimates of LC and breaking wave effects in terms of turbulence statistics for a wide range of wind and wave conditions. This work is an important step towards physics-based parameterizations of upper ocean turbulence, which are needed to improve numerical models of weather and climate.