How Mitie hired 360+ prison officers and cut new-joiner attrition to under 1%.

A prison mobilisation runs on a hard deadline. Mitie needed more than 360 staff recruited, trained, and ready, and the roles they were hiring for are among the most misunderstood in frontline work: physically and emotionally demanding, publicly stigmatised, and traditionally churning new joiners at 13.4% in similar roles. Every early leaver in a mobilisation isn’t just a cost, it’s a gap in a training cohort and a risk to the go-live date.

Attraction wasn’t the problem. Targeted social campaigns run with Equitas generated more than 7,000 applications. The problem was what to do with them. Manually sifting thousands of applications for roles this demanding would consume recruiter capacity the timeline didn’t have, and conventional screening couldn’t answer the question that mattered most: does this candidate actually understand what working in a prison involves? For roles where the gap between public perception and daily reality is this wide, that question decides who stays.

The brief to ThriveMap was specific. Screen at volume without burning recruiter time. Make sure every candidate who progressed had seen the reality of the role and chosen it anyway. And do it fast enough to fill training cohorts on schedule.

ThriveMap built the assessment in partnership with people who know prison environments first-hand, aligning it with Mitie’s values and the operational reality of the role. Rather than testing general knowledge or abstract reasoning, the assessment put candidates inside a simulated day in the life of a prison officer and scored them on the competencies the job actually runs on: communication, stress management, and judgement. Candidates watched realistic scenarios, a conversation with a prisoner refusing to leave their cell, a tense moment in the gym, and chose how they’d respond.

The assessment did two jobs at once. More than 5,000 applications were instantly screened, removing the manual sift entirely. And 9% of candidates opted out during the assessment itself, having seen what the role involves. Those were people who would otherwise have dropped out later, at the assessment centre, in training, or in their first months on the wing, after everyone had invested more.

The clearest way to see the impact is to follow the funnel downstream. Assessment centre attendance ran at 82%+, against an industry standard of around 50%: candidates who had seen the job and chosen to continue actually showed up. Pass rates at those centres exceeded 40%, double the historical average of 20%, because the people arriving had already demonstrated they could handle the role’s realities. Initial Training Course fill rates ran at 90%+, so cohorts went out full rather than padded with maybes.

The speed followed. Time to hire fell 45%, to under 5.7 weeks on average, on a project where the training calendar left no slack. And the number that matters most is the one still coming in: churn for new joiners currently sits below 1%, against a traditional average of 13.4% in similar roles. These are early cohorts, and the honest framing is early indicators rather than settled history, but an order-of-magnitude improvement on the sector’s attrition pattern is not noise.

The result nobody would have predicted was the candidate satisfaction score: 94.5%, with just 1% negative responses, for prison officer roles. These are jobs applied for against a backdrop of public stigma, where candidates arrive uncertain and half-expecting to be put off. Instead, they reported feeling respected, informed, and engaged.

The mechanism is the same one driving every other number on this page. The assessment treated candidates as adults making a serious decision, showed them the reality rather than a sanitised job description, and let them judge their own fit. For most applicants, it was the first honest picture of prison work they’d ever been given. One senior prison staff member put it plainly: “This should be used in every prison hiring process.”

For roles that struggle to attract and keep people partly because of how they’re perceived, a hiring process that candidates actively rate well isn’t a soft benefit. It’s the start of fixing the perception problem at its source.