These Ir(III) complexes exhibit outstanding photophysical properties – high photostability, long-lived phosphorescent excited states, tunable emission spectra,and high quantum yields – all dvantageous for PDT. An additional benefit is the structural tunability: by modifying the ligands, one can fine-tune the complex’s absorption/emission profile, ROS generation efficiency, water solubility, and even targeting properties. This flexibility enables with optimized efficacy and selectivity for cancer