James Foley’s research interests centered on understanding fundamental structure/function relationships pertaining to the photophysics that govern the properties and behavior of organic dyes. We use this knowledge to develop improved chromophores for use in biophysical, biological and medical applications such as single molecule detection, fluorescent reporting and photodynamic therapy. Their approach encompassed nearly every aspect that is essential to such an undertaking including computer-aided design, chemical synthesis and photophysical characterization of target dyes.