In the Wason-Selection Task debate it has been suggested that people may be able to detect cheaters but not co-operators or altruists. This position has been challenged. Here we focus on a scenario that is more ecologically valid with regard to different strategies for detecting workers who negatively interact with others (here ‘egoists’) and positive interactors (here ‘altruist’). The results on altruist detection in two-level personnel evaluation tasks (T-PETs), with information on individual and team performance, suggested a disregard of the team performance and a resulting “Tragedy of Personnel Evaluation”. Experiment 1 transfers the idea of altruist detection in a personnel evaluation and personnel selection task (von Sydow & Braus, 2016) to egoist detection and explores whether there are analogous problems for egoist detection. Experiment 2 explores egoist and altruist detection in more realistic settings where individual and group-selection may affect our sampling of the interactor.