The PicoHarp TCSPC module (PicoQuant GMBH) permits cross-correlation and autocorrelation analysis of intensity time-trajectories with resolution in the μs domain. The use of pulsed diode lasers (375 nm, 470 nm and 640 nm from PicoQuant GMBH) in combination with a nanopositioner (Physiks Instrument) and a time correlated single photon counting board (TCSPC PicoHarp, from PicoQuant GMBH)) further permits time resolved fluorescence spectroscopy, fluorescence lifetime imaging (FLIM) and time-tagged time-resolved measurements (TTTR). The Symphotime software developed by Picoquant permits the analysis and data acquisition for 1-D and 2-D measurements, TTTR analysis, and 2D FLIM analysis. The microscope consists of consists of an Olympus IX71 inverted fluorescence microscope provided with high NA oil immersion objectives. Sample raster-scanning is achieved with an x-y-z nanopositioner (Physiks Instrument). The detectors consist of avalanche photodiodes (Perkin Elmer) suited for single molecule measurements.