Medical professionalism is not just something you do—it is a way of being. It’s a lifelong process of becoming a better doctor, rooted in practicing medicine with integrity, purpose, and compassion. This chapter explores what it truly means to be a medical professional. It examines the ethical principles that form the foundation of medical practice, along with the ten professional commitments every healthcare provider accepts when entering the field. You’ll learn about core concepts such as patient autonomy, non-maleficence, beneficence, and the role of social justice in medicine. We trace the evolution of medical ethics from the time of Hippocrates to the present day, highlighting how the public’s perception of physicians has shifted over the past century. The chapter also introduces the Physician Charter on Medical Professionalism, created in 2002 by the American Board of Internal Medicine, the American College of Physicians, the American Society of Internal Medicine, and the European Federation of Internal Medicine. Finally, we confront a central question: Is medicine purely an altruistic calling dedicated to caregiving, or is it also a business designed to generate income and profit?