Using ground effect aerodynamics as the example, the essential role of both Experimental Fluid Dynamics (EFD) and Computational Fluid Dynamics (CFD) will be highlighted. Examples from our studies in this area include the analysis of a Formula-style front wing and wheel, the study of dimples and the study of compressible flow ground effect aerodynamics. In many cases, CFD has been used to not only provide complementary information to an experimental study, but to design the experiments. We have found that laser-based experimental techniques provide an excellent means to compare to CFD. We have developed a post-processing method, making use of the kriging and co-kriging estimators, to develop correlations between often disparate data types. Using the case of the wing and wheel as an example, one dataset is gained from the combination of both LDA and CFD results, using a co-kriging analysis.15 page(s