We propose a general method to find exact travelling and standing wave solu
tions of react ion-diffusion systems and nonlinear wave equations. The meth
od is applied to several well-known react ion-diffusion systems such as a c
ompetition-diffusion system of Lotka-Volterra type, the Gray-Scott model, a
simplification of the Noyes-Field model for the Belousov-Zhabotinskii reac
tion, and two- and three-component models for quadratic solitons. We also f
ind exact solutions of several generalized nonlinear dispersive equations o
ccurring in mathematical physics.