Ethics and responsibility are expressions that should characterize professional practice in many sectors of society. Pharmacy, being a high technology activity, is just an example of a field where (responsible) decisions about medicines and health care are closely connected to private and public life. Responsible behavior can only be demonstrated when the moral basis, the values on which decisions are taken, is clear and accepted by society as a whole. The basis for responsible action in medicine is still considered to connect with the Hippocratic Oath. But this code has no clear philosophical basis, other than the fact that it was recognized by the inner circle of physicians. Modern dilemmas like the role of technology, public costs, the definition of life, genetic engineering and assisted suicide ask for an approach that is rational, based on philosophical ideas and understandable and accepted by the public. From the work of 20th century philosophers like Rawls, Nussbaum and Sen, essential values can be abstracted, which apply to health and health care. Although the plurality of human beings makes it complicated to translate such values into general rules of conduct, this article presents a model for responsible behavior, based on these values. It appears that responsibility includes the obligation to interact with a patient to an extent in which the values of self-determination, compassion and justice have real significance for the parties involved. This responsibility calls for ('Aristotelian') experience and practical wisdom and should be recognizable through guidelines and legislation.