Polymersomes have been studied for many years since their discovery, and have consistently been an appealing and widely explored research domain. Their inherent benefits, encompassing stability, versatility, load-carrying capacity, and deformability, endow them with many opportunities to be used in numerous fields of biomedicine, nanocarriers, diagnostics and therapeutics. Nevertheless, shape transformation pathways have not been comprehensively summarized or received adequate scholarly attention. Herein, we summarize typical mechanisms underlying polymersome self-assembly with a particular focus on the shape transformation pathways associated with commonly employed self-assembling methods. Moreover, we provide a succinct overview of the proposed applications involving shape transformation applications, and enumerate the most recent findings in this domain.