This monograph explores the evolution of professional organizations, identities, and specialization, examining the historical trajectory, key drivers, challenges, and future implications of these interrelated processes. The work traces the shift from generalist occupational collectives to increasingly specialized professional identities and organizations, driven by factors such as the codification of knowledge, societal demands, technological advancements, and governmental interventions. It highlights strategies used by professions like medicine, law, and engineering to balance unity and specialization. The monograph also critically examines issues of professional ethics, social responsibility, and the need for greater diversity, equity, and inclusion in professional identity formation. Looking ahead, the work discusses how hyper-specialization presents both risks of fragmentation and opportunities for innovation, and calls for professional organizations to embrace interdisciplinary collaboration, public engagement, and a commitment to addressing complex global challenges. Ultimately, the monograph argues for a more expansive, socially responsive vision for the professions, and outlines educational and institutional reforms needed to support this evolution. The work represents an important synthesis of research on professional identity formation and specialization, and offers valuable insights for educators, organizational leaders, and professionals navigating the complex landscape of 21st century practice.