The Time Harp 100 single-photon counting board from PicoQuant GmbH is a complete system for time-resolved measurements on a single PC card. The solid-state design cuts costs, improves reliability and simplifies calibration. The circuit allows measurement rates up to 3 Mega counts per second in continuous mode and provides a time resolution of 60 ps. The input triggers are programmable for various input signals. The board is designed to work with the PicoQuant PDL 800 as an excitation source.