Three methods of kinetic spectroscopy using lasers are described. In the first, the infrared double resonance technique using two CO2 lasers has been used to examine the relaxation of both 11BC13 and 10BC13. The relaxation of the initially excited state to a distribution of excited states proceeds by a very fast V-V process at a rate of at least 2 x 10 6 sec-1 torr-1. The rates of deactivation of BC13 by the rare gases, HC1, DC1, H2, HD, D2, N2, CH3F, and CHC13 have been measured and indicate that rotational degrees of freedom in the collision partner play an important role in deactivation. Two other applications of lasers to kinetic spectroscopy will be described. A Q-switched CO laser is used to excite CO to its first vibrational level and subsequent relaxation of CO by D2CO is monitored by following the CO fluorescence. In another application, a nitrogen laser is used to dissociate H2 CO and the time-evolution of specific states of the CO produced is monitored by the absorption of CO laser light.