Since the dawn of molecular biology, cancer therapy has focused on druggable targets. Despite some remarkable successes, cell‐level evolution remains a potent antagonist to this approach. We suggest that a deeper understanding of the breakdown of cooperation can synergize the evolutionary and druggable‐targets approaches. Complexity requires cooperation, whether between cells of different species (symbiosis) or between cells of the same organism (multicellularity). Both forms of cooperation may be associated with nutrient scarcity, which in turn may be associated with a chemiosmotic (...) metabolism. A variety of examples from modern organisms supports these generalities. Indeed, mammalian cancers—unicellular, glycolytic, and fast‐replicating—parallel these examples. Nutrient scarcity, chemiosmosis, and associated signaling may favor cooperation, while under conditions of nutrient abundance a fermentative metabolism may signal the breakdown of cooperation. Manipulating this metabolic milieu may potentiate the effects of targeted therapeutics. Specific opportunities are discussed in this regard, including avicins, a novel plant product. (shrink)