The characteristics of a

-switched CO
2-N
2-He molecular laser are considered. In particular, it has been found that a 3-W continuous system gives a

-switch output power in excess of 10 kW per pulse. A method for determining rotational collision cross sections for CO
2is discussed, and an induced fluorescence technique is described which is capable of giving cross sections for vibrational relaxation in CO
2. The importance of various collisional coupling mechanisms and relaxation rates in determining total CW and

-switch output power is also considered.