An analysis of the performance of parameterizations for the drag coefficient C_D over the ocean is presented. The results were obtained by considering detailed observations from the recent IntOA experiment in which a co-existence of wind sea and swell provides characteristic mixed sea conditions in a wide range of wind speeds. Recent research has advanced our understanding of air-sea fluxes, proposing new functional forms for the drag coefficient, as well as applying wavelength scaling and determining dimensionally consistent expressions for the drag coefficient. Nevertheless, a detailed analysis of the influence of wind sea parameters confirms the need to include the sea state dependence on parameterizing C_D for mixed sea conditions. It is also shown that better results are obtained when aerodynamic roughness is considered as a function of wave age and wave steepness, or equivalently if C_D is expressed as a function of a characteristic peak frequency defined through the wave momentum spectrum.