Phil did his PhD on Bayesian Analysis of Clusters of Galaxies at the University of Cambridge, in which he first got interested in the process of measuring astronomical objects, including things like Dark Matter halos which we may not be able to observe directly. He first moved to Stanford in 2003 as one of KIPAC's first wave of postdocs, and returned as Kavli Fellow in 2009 after three years as TABASGO Fellow at the University of California, Santa Barbara. Phil then spent three years in Oxford as a Royal Society University Research Fellow, before moving back to join the SLAC staff on a permanent basis in 2013. He is currently Deputy Director of Operations for the Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST), thinking about how to set up the Rubin Observatory and its survey to successfully deliver the data products needed by, for example, the cosmology analysis planned by the LSST Dark Energy Science Collaboration (DESC). He helped form the LSST DESC at its inaugural meeting in 2012, and has held leadership positions in it ever since. Phil was LSST DESC Spokesperson in 2017-2019, during which time he led the implementation of the collaboration's operations plan.