Anyone wishing to use helicopters for public transport should have and Air Operators Certificate and Operators Licence.
The CAA have recently produced this leaflet. Unfortunately when it loads as a PDF it doesnt make sense at first until you realise page 1 is actual the second half;
http://www.caa.co.uk/docs/1196/20071...PRCampaign.pdf
The details listed previous are what the pilots must undertake prior to being allowed to fly passengers on public transport (based on a Single Pilot Day VFR Operation).