The search for the most effective method for the geometric parameterization of many internal fluid flow applications is ongoing. This thesis focuses on providing a general purpose automated parameterization strategy for use in design optimization. Commercial Computer-Aided Design (CAD) software, Computational Fluid Dynamics (CFD) software and optimizer tools are brought together to offer a generic and practical solution. A multi-stage parameterization technique for three-dimensional surface manipulation is proposed. The first stage in the process defines the geometry in a global sense, allowing large scale freedom to produce a wide variety of shapes using only a small set of design variables. Invariably, optimization using a simplified global parameterization does not provide small scale detail required for an optimal solution of a complex geometry. Therefore, a second stage is used subsequently to fine-tune the geometry with respect to the objective function being optimized. By using Kriging response surface methodology to support the optimization studies, two diverse applications, a Formula One airbox and a human carotid artery bifurcation, can be concisely represented through a global parameterization followed by a local parameterization.