This week-long workshop was dedicated to the recent developments in the study of jets as probes of QCD matter at high energies and densities. The workshop specifically focused on the use of jets to study the microscopic structure and transport properties of the Quark-Gluon Plasma (QGP) as well as the 3D structure of the proton/nuclei. Recent progress and future directions towards these objectives were discussed by theorists as well as experimentalists from RHIC and the LHC. The workshop was organized to allow ample time within each talk for questions, discussion, and brainstorming. This format facilitated numerous fruitful insights, fostering new ideas and connections between theory and experiment. Concurrently with this workshop heavy-ion collision data was being taken at the LHC, making it a timely event to propose new measurements that would shed new light on QCD at high energies and densities, especially in anticipation of the future Electron-Ion Collider.