The ongoing need for new agents to control weeds has stimulated the search for new photosynthetic inhibitors. We described in this chapter a variety of compounds presenting this type of activity. The natural products have been explored toward this end resulting in the identification of compounds with various structural motifs. Such an approach has resulted in the discovery of photosynthetic inhibitors with new modes of action. This, in turn, can be helpful in dealing whit resistance a problem to be faced in weed management
