In recent years, the overall mechanisms behind the antimicrobial activity of light alone have been relatively unexplored. However, recent studies on the interactions between light and pathogens have identified several endogenously expressed protective molecules that are extremely photosensitive and can be either inactivated or destroyed through light exposure. The photolysis of bacterial pigment molecules can allow for increased membrane permeability and lowered capability of resistance development, increasing susceptibility to antimicrobial agents while at the same time lowering its overall virulence. Furthermore, phototherapy can inactivate key antioxidant molecules like catalase and pigments, rendering both bacterial and fungal pathogens more susceptible to the toxic effects of reactive oxygen species. The applicability of this phototherapy technology on infected wounds has been found to be viable through the usage of wearable portable devices, demonstrating the strong potential of this technology among more clinical settings. Overall, the photoinactivation of endogenously expressed protective chromophores offers a noninvasive and nondrug-reliant method of directly targeting a broad range of pathogens. The following chapter and figures were primarily adapted from a review article published by Jusuf and Dong (Cells 12:2664, 2023).