The long-term interest of our research is in understanding the molecular mechanism of membrane-embedded proteins including ion channels, receptors, and transporters. The main biophysical tool we use to study these systems is solution NMR spectroscopy, although we use other high resolution techniques as appropriate for answering mechanistic questions. Our major challenge is to push the envelope of solution NMR to enable structure determination of alpha helical membrane proteins, not only by developing and testing new methods but also by applying them to address important questions in biology.