Combinatorial chemistry is a proven tool for lead generation and exploration in the discovery of novel therapeutic agents. In contrast, combinatorial chemistry approaches to lead generation for agrochemical discovery are in their infancy. This report summarizes the first reported examples of the application of combinatorial chemistry or parallel synthesis to the discovery of new fungicides, insecticides, and herbicides for crop protection. The synthesis and biological activity (
in vitro
or
in vivo
) of each compound library is described. The examples include the synthesis and testing of libraries of discrete small molecules as well as the preparation of pools of compounds and subsequent deconvolution of the active pools. Compound classes covered include amides, esters, ureas, N‐substituted glycines and 2‐amino‐4‐aryloxypyrimidines. These examples clearly demonstrate the potential of the technology to significantly impact the discovery of crop protection chemicals in the coming decade.