Modeling and simulation approaches can greatly improve the efficiency of clinical drug development, leading to faster and better quantitative decision making, when properly applied. Different disciplines involved in drug development utilize modeling and simulation techniques as part of their methodological toolbox. This has led to some confusion, eventual misunderstanding and competition, but increasingly synergistic collaboration among disciplines. This presentation will discuss a case study based on a real fixed dose combination program in Type 2 Diabetes Mellitus in which modeling and simulation played a key role in the approval of the NDA. Collaboration among the different modeling disciplines involved was instrumental to the success of the project and will be illustrated and discussed in the talk.