A quasi-continuous, widely and rapidly tunable optical parametric oscillator (OPO) with high average power is described. A Cu-vapour laser pumped, tunable dye laser has been used to pump a LiNbO3 OPO at a repetition rate of 6 kHz. Rapidly tunable infrared radiation in the range of 0.83–2.42 μm has been obtained with average powers as high as 136 mW in the short-wavelength branch of the output.