The Personal Investment Authority (PIA) was the investors' watchdog dealing with all advisers who marketed products directly to the general public.
Since the Financial Services Authority assumed its full responsibilities in 2001, the PIA's role has been subsumed within the FSA.
If your financial adviser tries to sell you investments or savings products, he (or she) has to be registered.If he's not, and is not regulated by another appropriate regulator, he's breaking the law.
Bear in mind that if you lose money as a result of taking advice from someone who's not authorised, you're not entitled to any compensation from the industry-wide scheme.