This application note describes a fluorescence-lifetime detection system based on a fibreoptical probe with an exchangeable tip. The excitation light is delivered to the tip via a single-mode fibre, the emission light is transferred to the detector by a multi-mode fibre. The electronic part of the system consist of a bh BDL-SMN picosecond diode laser, a bh PMH-100 hybrid detector or MW FLIM GaAsP multi-wavelength detector, and a Simple-Tau 150 TCSPC system. The system features high sensitivity and short acquisition time. Clean fluorescence decay curves from a 10-7 mol/l fluorescein solution were recorded within an acquisition time of 0.5 seconds, time-series of autofluorescence decay curves were recorded at a speed of 100 ms per step.