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Set up 301 Redirects on pages which are similar. I.E. Personal Trainers redirects to Who's Who page for example. Once the traffic has started to go to the new site Google will start to list the new pages. And Visitors will start to realise it's the new site. Also put a big graphic on the old site saying we've moved to and link to the new site. Do a search on a search engine for the old domain and ask sites to change the links, Ensure that any well ranked pages are moved across to the new site, (if it worked before it could work again!) Once your traffic has fizzleed out on the old site redirect the domain as a 301 to the new site.