It was clear from the number of attendees and the broad spectrum of organizations represented at this conference, that effective formulation development for biopharmaceuticals is a critical and timely issue. From DNA-based products to antibodies, vaccines to therapeutics, administered by every route known to medicine, formulation plays a critical role in the ultimate success of biopharmaceutical products. It was obvious from the various case studies presented that effective formulation development is not often achieved as an organization enters into drug development. In fact, systematic pre-formulation work was stressed by most speakers as an effective use of company resources. In order to develop successful formulations, it is essential that appropriate analytical information is collected, that excipients are systematically evaluated, and that the developer understands the basis of stability of the drug product. In all cases, this means understanding product instability, including the physicochemical and thermodynamic basis for instability. Drugs such as therapeutic antibodies, which may require large doses to achieve the desired pharmacological effect, require ever more advanced formulation development to achieve concentrations in the 100-mg/ml range. Potent drugs, such as gene therapies and DNA vaccines, require formulation development in order to achieve effective delivery and expression. On aggregate, it is apparent that there is much to learn in formulation development, from each other as well as in the unexplored territory ahead. This conference provided an excellent forum for the exchange of ideas and information regarding effective formulation development for biopharmaceuticals.