Hi headbocs,You're not on your own being in this position. I'm also looking to move from a senior role in the NHS to one of the big 4 (I'm in the final stages of the interview process now) after completing my Doctorate, and I'll be 26/27 when I start if I get the job. Due to my lack of consulting experience in a commercial environment, I've had to apply at a junior level also.Whilst I can't speak from direct experience, I have spoken to several other people who have gone into a career in consulting and other service lines in the big 4. Their experiences were generally along the lines of occasional frustration due to having nailed down the generic work skills others did not have. However, they noted that overall there were not hugely noticeable differences, and in fact junior colleagues could contribute in areas where they could not.I think in relation to the progression, whilst I would be cautious in buying into any spiel about assured, accelerated progression, again the experiences of the people I have spoken were that their prior knowledge and work experience put them in a good position relative to their peers. This often translated into favourable performance, which would obviously make you stand out as others have said, as progression is largely (though not entirely) based on your performance and ability.CP