Spectroscopic techniques, especially infrared (IR) spectroscopy, can give specific chemical information, identifying intermediates and products during extremely fast reaction based on the spectral information collected. Modern FT-IR (fourier transform infrared) spectrometers have fast scan capabilities allowing for fast chemical reactions to be monitored in real time. The coupling of an FT-IR spectrometer with a stopped flow system can generate significant spectral and chemical information whilst retaining the integrity of the fast chemical reaction. This application note describes how the PerkinElmer Spectrum 3 equipped with the stopped-flow system provides valuable information on rapid kinetic experiments.