Femtosecond transient hole burning spectroscopy and stimulated photon-echo peak-shift spectroscopy can be used at physiological temperatures to examine solvation-like dynamics inside of proteins in response to charge transfer or light-induced dipole-moment changes. We have characterized the solvation dynamics exhibited by several types of protein systems, ranging from small globular proteins to membrane proteins in detergent environments. All of the systems exhibit an inertial response on the sub-100-fs time scale that is assigned to librational motions of nearby polar groups or intrinsic water molecules. A diffusive response, assigned to conformational motions, extends over many orders of time scale beginning with the picosecond time scale. The diffusive part of the response is sensitive to the fast motions of molten globule structures that are distinct from those of native structures.