There is considerable interest among pharmaceutical and other medical product developers in adaptive design clinical trials. The recently passed 21st Century Cures Act also encourages a broader use of adaptive design in clinical studies. A 6-year (2008-2013) retrospective survey was performed within the Center for Biologics Evaluation and Research (CBER) at the FDA to gather information regarding the submission and evaluation of adaptive design trial proposals. In this talk, we will present a summary of adaptive design proposals seen in CBER and provide an overview of our experiences. We share our concerns regarding the statistical issues and operational challenges raised during the review process for adaptive design trials. We will also provide general recommendations for developing proposals for such trials.