Proteases are essential ingredients in modern laundry detergents. Over the past 30 years, subtilisin
proteases employed in the laundry detergent industry have been engineered by directed evolution and
rational design to tailor their properties towards industrial demands. This comprehensive review
discusses recent success stories in subtilisin protease engineering. Advances in protease engineering for
laundry detergents comprise simultaneous improvement of thermal resistance and activity at low
temperatures, a rational strategy to modulate pH profiles, and a general hypothesis for how to increase
promiscuous activity towards the production of peroxycarboxylic acids as mild bleaching agents. The
three protease engineering campaigns presented provide in-depth analysis of protease properties and
have identified principles that can be applied to improve or generate enzyme variants for industrial
applications beyond laundry detergents.