This book brings together the central tenets of William Stern's critical personalism. Presented for the first time for an English-speaking audience, this selection of original translations and essays encapsulates the critical framework of Stern's personalistic psychology. The selected works highlight the philosophical basis of Stern's personalistic views, illustrate their relevance in domains of theoretical and practical importance in psychology, and reveal Stern's critical stance on certain methodological trends that were gaining favor within psychology during his lifetime. Lamiell's own chapters contextualise the translations by providing an overview of the most basic tenets of critical personalism, and offering a commentary on paradigmatic commitments within scientific psychology's mainstream that began to impede Stern's efforts prior to his death, and that remain obstacles to personalistic thinking in the discipline today. Largely ignored by his contemporaries, this work forms part of an emerging body of scholarship that seeks to reintroduce Stern's thinking into contemporary psychology. The book is intended for academically oriented scholars with interests in historical, theoretical and philosophical issues in psychology.