This document discusses Raman spectroscopy and its applications for medical diagnostics. It provides an overview of Raman spectroscopy principles and instrumentation. It then discusses various applications of Raman spectroscopy including in-vitro biofluid assays, in-vivo cancer detection using probes, and real-time Raman systems for skin cancer diagnosis. Raman spectroscopy is shown to be useful for applications ranging from laboratory testing to real-time clinical cancer detection.