This thesis seeks to examine how funding arrangements for cancer drugs and other treatments, which are not available to everyone within the NHS, are made available to some, on the basis of exceptionality. The escalating costs of cancer treatment and the life threatening nature of cancer make resource allocation decisions for cancer drugs particularly acute, and the recent changes to funding arrangements for cancer drugs within the NHS receive particular scrutiny.In the three papers at the core of this thesis, the concept of exceptionality is explored from legal, ethical and empirical perspectives respectively. The first paper reviews the legal origin of exceptionality as the basis for the allocation of resources for expensive treatments, and explores how the concept has been interpreted by successive judicial reviews concerning access to cancer drugs. Particular attention is paid to the role of social factors in determining exceptionality. Choosing to fund treatment for one patient, and not another, involves a moral choice. In recognition of this, the Department of Health advocates that decision makers use an ethical framework to support decision making regarding exceptionality. The second paper examines the strengths and weakness of Daniels and Sabin's Accountability for Reasonableness Framework, which is widely used to support resource allocation, focussing on the Relevance Condition, and its applicability to resource allocation within the NHS. The final paper reports the findings of an empirical study examining how PCTs interpret the concept of exceptionality in practice, providing the first comprehensive insight into the factors which are considered in determining whether a patient is exceptional, and exposing some of the external influences on the decision making process. In conclusion, it is argued that whilst the need for discretionary health funding decisions arises in rare circumstances, where this is necessary such decisions should be made on a national, or at least supra-regional basis, to ensure consistency and fairness. If we cannot afford to fund all effective cancer drugs, and other treatments, we should not hide behind the concept of exceptionality, but should have a national debate about how we reach a consensus on which drugs to fund, and about how we pay for those treatments. Whilst acknowledging that cancer is a dreadful disease, it is also argued that, in the absence of any convincing evidence that the management of cancer deserves preferential treatment, the special status of cancer funding within the NHS, which has become increasingly apparent in recent years, should come to an end.