This dissertation explores the relationship between pharmaceutical marketing strategies, physicians’ core professional values, and their prescribing behavior. Grounded in the principles of healthcare marketing and ethical decision-making, the study examines how physicians respond to external promotional efforts while maintaining their internal value-based approach to patient care. Using a quantitative methodology (survey), data were collected from a sample of physicians in Athens to test three hypotheses regarding segmentation based on core professional values, preferred marketing strategies, and prescribing behaviors and the influence of professional values and marketing strategies on prescribing patterns (brand or/and price considerations). The results provide evidence that physicians are not a homogeneous group, rather, they can be segmented based on their ethical and professional orientations. Core values such as respect from the patients and patient-centered relationships play a significant role in shaping prescribing choices, while marketing strategies exert varying degrees of influence. These findings offer important implications for healthcare marketers and policy makers seeking to understand the dynamics of physician behavior within an ethical and professional framework.