Since the early twentieth century the PhD has been the research degree of choice in the UK, but traditional ideas and practices relating to the degree are now being challenged. This paper sketches out the main drivers of change and explores the main challenges confronting doctoral study within the UK. It explains why there is a need for a wholesale revision of assumptions and expectations about what the PhD is, and it charts the genesis and evolution of the PhD in the UK. Key drivers for change include new emphasis on skills and training, submission rates and quality of supervision, changes in the examination of the thesis, and the introduction of national benchmarking. The paper then explores changes in the PhD as product and as process, and outlines how and why new forms of doctorate are emerging. It asks, rhetorically, whether the changing nature of the doctorate reflects adaptation to changing circumstances in order to survive.