A tandem PPLN and ZGP optical parametric oscillator (OPO) has demonstrated the generation of multiple wavelength output in the mid-infrared. A pulsed Nd:YVO4 laser, oeprating at 1.342 microns, pumped a PPLN OPO that generated 2.12 microns and 3.66 microns. 8.4W of 1.342 microns was available at the PPLN. The PPLN OPO produced 2.6W at 2.12 microns, of which 2.35W was available to pump the ZGP OPO. The ZGP OPO generated a total combined output of 0.85W at 3.9 microns and 4.6 microns. The threshold of the ZGP OPO was measured to be 60 micro-Joules (10.6 MW/cm2, ~18 ns FWHM pulse).© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.