The design and performance of a high-power synchronously pumped dye laser is described. Emphasis has been given to achieving bandwidth-limited and diffraction-limited performance so that efficient, reproducible nonlinear frequency conversion can be achieved. Pulses of 1 mJ from Rhodamine 6G and 250 μJ from DCM with tuning ranges of 557-584 nm and 609-676 nm, respectively, have been obtained. Second harmonic generation with 40 percent efficiency to ∼ 280 nm and efficient multiple Stokes Raman shifting to cover the range m has been demonstrated. Blue dyes, pumped by third harmonic of Nd:YAG, have been operated. Typically, for Stilbene 3 (peak at 420 nm), pulses of 160 μJ were obtained.