In the application of lasers in such fields as nonlinear optics, one is often faced with the problem of limitation in the highest available laser power. A potential solution to this situation is to achieve higher power by adding separate lasers in parallel. However, whether such schemes would have an inherent limitation imposed by the lack of coherence of separate lasers is not so obvious. We have found that separate lasers can indeed be used as uncorrelated pump sources for parametric interactions. For optical parametric oscillations, each additional pump for amplification (with Stokes radiation) would enhance the exponential gain and reduce the oscillation threshold. Conversely, each additional pump for up‐conversion (with anti‐Stokes radiation) would reduce the exponential gain and raise the oscillation threshold. The contribution of each elementary scattering process can be evaluated individually allowing the net effect to be summed together in simple expressions.