The UK model and the US model are very different when it comes to post-grad training. In the UK it takes much longer to get trained. New grads to a house year of 6 mos medicine and 6 mos surgery. They then become SHOs and spend 3-5+ years working at hospitals in various specialties depending on their interests and getting ready to take the membership exams (MRCP, MRCS, MRPsych, etc.). Then they try to get "a number" to become a registrar, a position that will train them to become a specialist (pulmonogy, nephrology, surgery, etc). This can take a while, depending on competitiveness of the field. Once they have become a reg, they are there for 5+ more years before they take their exams to become a consultant. It takes much longer to train. Moreover, the NHS must have a job for you to go to. Preceding all of this requires you to pass the PLAB exams (written and clinical skills) so you are eligible to apply for jobs in the UK. Jobs typically last from 6 mos-2yrs and you may move around a fair bit. As for coming back to the US, I knew a pediatric cardiologist who finished his training and then because the NHS had no positions, he worked at USCF for 6 mos and then went back to London because a spot opened up. The shortest programs are those for GPs; takes 4-5 years to complete that track, but they have NO hospital practice whatsoever when they are finished.