The first part of the programme isstructuredand requires you to take a certain number of course modules, begin research with your supervisor and pass what is called a confirmation. You must complete this part of the course within 18 months of first registration if you are a full time student, and within 30 months if you are a part-time student.
After completing the first part then you enter the second part of the programme where you concentrate wholly on the research for your thesis. This finishes when you submit the thesis and it is passed in the thesis examination (or viva). This is normally done within 4 years for full-time students. If you need longer to submit the thesis then this must be approved each year by the Dean of Graduate Studies (a process called continuation).