TASI 2015: New Frontiers in Fields and Strings: Proceedings of the 2015 Theoretical Advanced Study Institute in Elementary Particle Physics, Boulder, Colorado, 1–26 June 2015

This volume is a compilation of lectures delivered at the TASI 2015 summer school, 'New Frontiers in Fields and Strings', held at the University of Colorado Boulder in June 2015. The school focused on topics in theoretical physics of interest to contemporary researchers in quantum field theory and string theory. The lectures are accessible to graduate students in the initial stages of their research careers.