Pulsed short-arc xenon flashlamps are used as the source of optical radiation in many analytical and life science instruments. They provide useable energy from below 150nm to over 1100nm. As a pulsed source they can operate at high peak power while still maintaining a low average power. The electrical operating conditions play a major role in the final performance of the lamp. This paper will look at the effect on electrical to optical conversion efficiency, arc size, and spectral distribution of varied electrical operating conditions. Some "rules of thumb" will be developed for the above characteristics as a function of electrical operating conditions. Specific attention will be paid to the new generation of smaller sized flashlamps.