http://en.wikipedia.org/wiki/Specialist_registrar
A Specialist Registrar or SpR is a doctor in the Republic of Ireland and formerly in the United Kingdom who is receiving advanced training in a specialist field of medicine in order eventually to become a consultant. After graduation from medical school, they will have undertaken several years of work and training as a pre-registration house officer and senior house officer, and will usually have taken examinations for membership of the Royal College of their speciality. For example, medical registrars will take the MRCP examinations to enable progression to become registrars.
Specialist Registrars generally stay in post for around five years (more or less depending on the speciality), gaining experience in a broad speciality (e.g. general medicine), and in a subspeciality (e.g. cardiology) after which they receive the Certificate of Completion of Training (CCT). The CCT is awarded based on satisfactory yearly Record of In Training Assessments (RITA) and completion of an 'exit' exam or fellowship diploma in the specialty from one of the Royal Colleges. Listing on the Specialist Register permits application to consultant jobs. Specialist registrars are encouraged to undertake research in their field, and many choose to do this by means of a PhD or MD.