Proteins are becoming increasingly important as therapeutic agents. Due to their inherent instability, proteins present a unique challenge in the development of stable formulations. We study the mechanisms by which proteins are damaged in liquid and dried formulations, and the mechanisms by which additives inhibit this damage. Our work on protein aggregation includes not only studies on therapeutic proteins, but also investigations into the amyloid fibril formation by proteins involved in human diseases such as systemic amyloidosis and Parkinson's disease. In addition, we are studying the use of high hydrostatic pressure to disaggregate and refold proteins.