Abstract: An end-pumping laser system, which includes a resonator and a single pumping radiation source. The resonator includes an input coupler, a lasing medium and an output coupler. The single pumping radiation source pumps radiation axially into the resonator. The input coupler of the resonator is a retroreflector having three orthogonal surfaces which is located coaxially with, and intermediate between, the resonator and the pumping radiation source. The retroreflector is oriented so that radiation from the pumping radiation source simultaneously impinges on the three orthogonal surfaces of the retroreflector.