Bogus Callers are conmen (or women) who use a variety of stories to gain access to the home in order to commit burglary.
They may pose as an official caller from a local authority or a utility company with a plausible explanation for needing to enter the house.
These pages will give you information on how to identify and deal with bogus callers. You can also find out more about the SeniorLink Bogus Caller scheme run by Help the Aged.