Renewal was set up in 2013 and has not had any comms support in place until now.
WPI told PRWeek the brief included raising the profile of the campaign group and the issues it is promoting in the national print and broadcast media. It is also tasked with helping Renewal develop its digital presence.
David Skelton, founder and director of Renewal, said: "The aim of Renewal is to try to tackle the cultural and often historic barriers that prevent people from identifying themselves with the party. It is imperative that we build on the success of 2015 and make further inroads into Labour's heartlands.
"In order to achieve this mission we need to improve the way we as an organisation communicate our ideas to MPs, the media and of course the public. That is why I am delighted that Westminster Policy Institute has agreed to come on board."