These proceedings present a comprehensive overview of recent ATLAS measurements of collective flow phenomena in a variety of collision systems. Measurements of the mean, variance, and skewness of the distribution of event-by-event per-particle average transverse momentum are reported for Pb+Pb collisions at $\sqrt{s_{NN}}=5.02$~TeV and Xe+Xe collisions at $\sqrt{s_{NN}}=5.44$~TeV. These measurements give insight into the nature of the spatial energy fluctuations in the QGP produced in heavy ion collisions. Measurements of the azimuthal anisotropy of high-\pT particles in Pb+Pb collisions, using two and four-particle cumulants are presented. The harmonic flow measurements in high-\pT provide information on the path-length dependence of parton energy loss in the quark-gluon plasma. Two sets of measurements that investigate if the presence of jets affects the flow-like behavior observed in \textit{pp} collisions are also presented.