Uses ultrafast multidimensional spectroscopy to study structural dynamics of biomolecules. Directions: (1) 2D IR spectroscopy of protein folding, water dynamics, and membrane systems with sub-100-fs time resolution; (2) single-molecule FRET for resolving conformational heterogeneity in proteins and nucleic acids; (3) development of ultrafast mid-IR laser sources and pulse shaping for 2D spectroscopy. Resolves dynamics inaccessible to other methods.