Jonathan Gair leads a research group on "Data Analysis". His research is in the development and application of new methodology for gravitational wave data analysis and science exploitation. He is playing a leading role within the LIGO/Virgo collaboration in deriving constraints on cosmological parameters, such as the local expansion rate of the Universe (the Hubble constant), from gravitational wave observations. He is also heavily involved in the development of data analysis tools for, and assessing the potential scientific impact of, the planned ESA-led space-based gravitational wave detector LISA and currently chairs the LISA Science Group which oversees that activity. Jonathan Gair also has completed research projects connected to gravitational wave detection with pulsar timing and astrometric measurements, and on the development of computationally efficient techniques for parameter inference.