The presentation will start with a brief historical introduction to coherent Raman spectroscopy with particular emphasis on the physical basis of the scattering. Then it will be shown that a few significant findings of his former pioneering results of applications of the method on photoactive proteins got support from recent time-resolved X-ray diffraction measurements. The tasks needed to get reliable measurements and the necessary data processing of coherent Raman spectra will be discussed. His recent recognition of the usefulness of 3-color two-beam coherent Raman scattering to measure low-frequency vibrational spectra will be detailed. The lecture will describe the necessary steps to apply the method to measure low-frequency phonon spectra of crystalline samples and present the first results on unique crystals.