This chapter will examine the ways in which ethical issues are part of the practice of medicine. In this fi rst section we will look, briefl y, at a number of ethical theories and concepts and the ways in which they might relate to medicine. Next, we consider the doctor–patient relationship and the way in which medicine has given rise to particular ways of describing this relationship and its ethical implications. Although it is by no means a clear-cut dichotomy, generally it can be said that many of the problems in medical ethics, and certainly many of the confl icting opinions, are based upon the debate between paternalism and the patient’s right to autonomy. First, the view that paternalism is central to the doctor–patient relationship means that because of the doctor’s superior knowledge and his ethical obligation to do good, the medical view of what is best for the patient should prevail. The opposing view is that the patient has a right to autonomous decision-making and that this should not be overridden by ‘doctor knows best’. Later in the chapter we will study these two different ways of looking at the doctor–patient relationship, question whether it is helpful to use either of these models as frameworks for medical decision-making, and look at alternatives. Finally, we will look at justice and fairness in the allocation of treatment between competing patients when resources dictate that not all can be treated, and at the distribution of health care resources on a national level. However, although the current chapter looks at general principles, when appropriate, ethical problems in particular areas of medical practice will be examined in other chapters.