Structure of a Research Degree
A PhD involves the production of a thesis, and takes three years of full-time or five years of part-time study.
The MPhil or LLM by research also involves the production of a thesis, but takes one year of full-time or two years of part-time study.
The great advantage of pursuing a degree by thesis is the freedom which it offers, in choosing your topic of study and in designing your research method.