One of the more interesting debates in human resources over the course of the pandemic has been on rehiring employees who have left an organization. A quick search results in a long list of articles that present the pros and cons of what are typically called "boomerang" employees. The broad consensus of the articles in favor of the practice suggests that an employee who returns to an organization can help demonstrate that the job market is not as good as expected and that the company she returns to is a better alternative than others.

It is not difficult to imagine the reasons why boomerang employees may seem attractive to a hiring manager. Former employees are well-known to the organization, so the risk of getting an unexpected outcome should be lower. They understand the company culture and business, and thus they should require less time and effort from their rehire date to reach full productivity. Often, they are known to and liked by current employees. For these and other reasons, a practice that was once almost unheard of has been gaining in popularity, especially given the recent staffing shortages many companies are facing. In fact, many organizations, notably in the high tech and consulting sectors, maintain "alumni" networks to keep former talent aware of new opportunities and to make it easy for them to return to a former employer. 

Despite the seeming attractiveness of rehiring a former employee who left on good terms, behavioral consistency theory suggests that past behavior is a good predictor of the future. Someone who found reasons to leave an organization in the past is likely to find reasons to do so again. Likewise, an employee who was not worth keeping not too ago is unlikely to have transformed into a must-have human capital asset. 

Surprisingly, given the strong reasons for and against hiring former employees—and also the rising levels of boomerang hiring—serious analyses of the phenomenon are hard to come by. Almost all hiring literature on new employees assumes they are just that—new—and ignores what happens when former employees are rehired. Likewise, almost all literature on promotions assumes candidates are either (true) new hires or internal candidates. A new paper from John D. Arnold (Missouri), Chad H. Van lddekinge (Iowa), Michael C. Campion (UT Rio Grande Valley), Talya N. Bauer (Portland State), and Michael A. Campion (Purdue) provides what may be the first systematic analysis of boomerang employee performance, and it should become required reading for hiring managers considering bringing back former employees.