Chemists at ITbM, Nagoya University have developed a super-photostable fluorescent dye called PhoxBright 430 (PB430) to visualize cellular ultra-structure by super-resolution microscopy. The exceptional photostability of this new dye enables continuous STED imaging. With its ability to tag proteins with fluorescent labels, PB430 demonstrates its use in the 3-D construction and multicolor imaging of biological structures.