A comprehensive discussion of professionalism in medicine must include its impact on successive generations of physicians. Fifty years ago, doctors acting professionally emphasized medicine as a calling and an ability to act as the authority for patients in crisis at home and in hospitals. Therapeutic options were limited relative to the modern era, and the laying on of hands was practiced as science and art. Today, doctors balance increasing demands on time and efficiency with the sense of primacy of patient care. Technological innovation and patients’ increasing access to medical knowledge through varying media of inconsistent quality challenge physicians in novel ways. Fifty years in the future, doctors will have access to vast amounts of information through a multitude of noninvasive diagnostics. Progressively more personalized medicine should inspire doctors to become even more adept at communicating effectively with patients. Professionalism in medicine throughout these generations embodies similar fundamental behaviors, such as demonstrating compassion, respect, and humility; adhering to high ethical and moral standards; subordinating personal interest to that of others; and reflecting on actions and decisions. Despite the dynamic nature of the profession itself, the omnipresent need for such traits will define medical professionalism for decades to come.