PowerLab (before 1998 was referred to as MacLab) is a data acquisition system developed by ADInstruments comprising hardware and software and designed for use in life science research and teaching applications. It is commonly used in physiology, pharmacology, biomedical engineering, sports/exercise studies and psychophysiology laboratories to record and analyse physiological signals from human or animal subjects or from isolated organs. The system consists of an input device connected to a Microsoft Windows or Mac OS computer using a USB cable and LabChart software which is supplied with the PowerLab and provides the recording, display and analysis functions. The use of PowerLab and supplementary ADInstruments products have been demonstrated on the Journal of Visualised Experiments.