The agency will work closely with the Tollejo Media Group, which runs industry blogs such as Mobile Industry Review.
Parys wants to help companies target the most appropriate forms of social media.
Tollejo will concentrate on teaching executives about the importance of social media and training them to create blogs. It will also build digital media for companies.
Anthony D'Alton, director at Parys, said: 'While social media is not a new part of PR it is often still seen as something of a dark art. Hopefully we can help change this perception by providing clear and honest advice.'
Blogger Ewan MacLeod and journalist Dan Ilett are behind Tollejo. MacLeod claimed that many PR agencies did not understand the blogosphere.
He said: 'You see some companies reacting to social media and others that do not, and it can result in a difference in profit.'
MacLeod stressed the importance of two-way comms and it was not enough anymore for agencies to simply put out news. 'When you've got bloggers and sites such as Facebook talking about your company you need to be in the conversation,' he said.