The agency will oversee a strategic comms and community engagement programme around the proposed new Waterside campus development.
The university is seeking to create the single campus within the Northampton Waterside Enterprise Zone.
Subject to planning permission, it is hoped that the university will start groundwork in 2014, with the campus opening in autumn 2018.
Communications Management, which last year supported the university's successful application to build its St John's Hall of Residence in Northampton town centre, is initially working towards the university's outline planning application for Waterside.
Included in work overseen by the agency’s specialist community engagement team will be managing stakeholder relations and contributing to public consultations.
Jayne Hoskins, assistant director for marketing and comms at the University of Northampton, said: ‘Communications Management impressed us tremendously with its work on the St John's Hall of Residence last year, working intensely and to a short deadline to help the university get planning permission for that development and dealing with some highly contentious issues effectively along the way.
'The Waterside development is absolutely critical to the university's future growth plans, and we had no hesitation in asking Communications Management for its support in delivering this piece of work for us. Its team is highly skilled, extremely proactive and responsive and has quickly become an extension of our own team.’