This book offers a rigorous reappraisal of two of the most influential metaphysical thinkers of the twentieth century. Drawing on close readings of Alfred North Whitehead and Gilles Deleuze, Ian Patrick McHugh examines how each philosopher accounts for relations, relationality, and continuity within a philosophy of becoming. Arguing that Whitehead provides a more coherent and systematic explanation of relations through actual process than Deleuze's account based on differential relations, the book develops a sustained comparative analysis of their respective ontologies. It also reassesses key concepts including continuity, possibility, value, actuality, difference, and process, while advancing an original constructive proposal that engages with Peirce, Leibniz, F.H. Bradley, and Alexius Meinong. The volume will be of interest to scholars and graduate students working in metaphysics, process philosophy, continental philosophy, and Deleuze studies.