A promising new greener way of cleaning up crude oil spills on water has been developed. Oil spills in waterways are major threats to the environment. One way they are currently remediated is by using silicone-based “chemical herders” to contract and concentrate the oil so it can be burned off. But these chemical herders are nonbiodegradable and thus persist in the environment, so questions have been raised about whether the cure they provide exacerbates the disease they are designed to treat. Now, George John of City College of the City University of New York and coworkers have made two cationic amphiphilic agents, PIm and PPy, that round up oil spills about as well as the best silicone-based chemical herders but are biodegradable (Sci. Adv. 2015, DOI: 10.1126/sciadv.1400265). They each contain an ester-allyl group that hydrolyzes in water, causing the agent to break into two parts—a phytol that persists long enough to help maintain herding action but eventually degrades and a brominated cation that dissolves in water. These green herders could be “safe and effective oil-spill mitigation chemicals for a sustainable future,” the researchers write.