The Primordial Mind in the Work of Wilfred Bion: Between Light and Shadow explores Bion's concept of the primordial mind and its profound impact on psychoanalytic clinical practice. Drawing on Bion's groundbreaking later works to illuminate the origins of mental formation, Gisele Brito provides clinicians with essential insights into primitive mental states and their clinical manifestations in contemporary psychoanalytic practice. Through detailed exploration of concepts such as the caesura, β Elements, primitive moral conscience and the urge to exist, readers gain practical understanding of how to contain and approach devastating primordial forces. The book combines theoretical advancement with clinical fragments and Bion's supervisions, offering concrete tools for working with patients experiencing extreme psychic suffering and mental states that disrupt analytical progress. Written for trained psychoanalysts and advanced Bionian scholars engaged in clinical practice and theoretical research, this work serves those seeking to expand their understanding of primitive mental states and the origins of psychological development in analytical settings.