Peroxidases can inactivate the colored dyes that leach out of clothing during the wash, and variants able to withstand the harsh environment of the washing machine are sought by the detergent industry. Directed evolution is a powerful means of altering enzymes to perform under such non-physiological conditions, and in this issue, Cherry et al. use this technology to evolve a highly stable peroxidase from inkcap mushrooms that is ideally suited for laundry detergent applications (see pp. 333 and 379).