The ICH Q8 FDA Guidance for Industry defines "Design Space" as: "The multidimensional combination and interaction of input variables (e.g., material attributes) and process parameters that have been demonstrated to provide assurance of quality." Working within the design space is not considered as a change, and hence needed modifications within the design space can be made without formal regulatory approval. As such, construction of a design space for pharmaceutical development is important. The talk presents a flexible Bayesian approach to constructing a design space based upon the concepts in Peterson (2004).