The win follows a four-way shoot-out against Tullo Marshall Warren, Craik Jones Watson Mitchell and Publicis Dialog.
The review, which was first reported by Brand Republic, was called by the COI in April, and tasked the shortlisted agencies with producing plans to increase the number of vacancies advertised through Jobcentre Plus.
The first creative work from Kitcatt Nohr is due to appear later this year. The campaign will focus on increasing brand awareness and influencing a positive brand perception among employers.
Marc Michaels, COI director of direct and relationship marketing, said: "There is a need to shift the perception of JobCentre Plus among employers and, as a result, increase the number of appropriate vacancies placed.
"We selected Kitcatt Nohr for the job because of its insight into the business audience and its strategic approach to media. Achieving the right tone of voice and creating good copy is critical to success and the agency was able to demonstrate success in this area."
Manning Gottlieb OMD worked with Kitcatt Nohr on media planning for the pitch.
Job Centre Pus is the largest recruitment agency in the UK, offering a complementary channel for employers.
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