While interest in the application of self-assembling ring polymers in drug-delivery applications is building, there is a relative lack of detailed understanding of the molecular-scale mechanisms that drive the emergence of their desirable properties. Molecular-scale simulations present the unique opportunity to build this level of understanding. Simulations have recently been used to develop understanding of the unique properties of ring polymers within polymeric melts, extensional flows and thin films. However, relatively few simulation studies have investigated the underlying mechanisms that lead to the properties of ring polymers in aqueous environments observed experimentally. Studies that have been performed have primarily utilized coarse-grain polymer models to gain insight into how polymer topology affects the morphology of the micelles that form. In this manuscript, we employ all-atom molecular dynamics simulations to gain a de-tailed understanding of the atomistic interactions and molecular mechanisms that drive the self-assembly of a ring polymer consisting of poly(methyl acrylate) and poly(ethylene oxide) blocks (-(MA 12 EO 31 -)) in comparison to its analogous linear triblock topologies (MAterminated (MA 6 EO 31 MA 6 ) & EO-terminated (EO 15 MA 12 EO 15 )) (see Figure ). We provide a detailed description of the internal structure of the micelles that each polymer forms, which plays a key role in drug solubilization, as well as the stability of micelles as drug delivery vehicles.