Our research focuses on understanding structure-function relationships in organic semiconductor materials from the nano- to microscale size ranges. We are particularly interested in conjugated polymer molecules that are candidate materials for use in field- effect transistors, light-emitting diodes and solar cells. The manner in which polymer molecules fold and pack has a profound influence on rates and distance scales of key electronic processes, such charge and energy transfer. We use advanced single molecule and spectroscopic imaging techniques to unravel complex structure-dependent photophysics in various polymer functional forms. In addition, we are able to simultaneously measure electrical properties in model device structures to establish true structure-function correlations not available from other physical techniques. Students involved in this research work in a highly multi-disciplinary environment and benefit from working on technologically relevant problems of great importance to society.