The study examines which understanding of rationality is expressed in the Swedish Agency for Economic and Regional Growth's evaluation processes and how rationality is manifested. The logic of consequences and the logic of appropriateness are used to interpret what rationality within the administration means and how it can be understood in the context of evaluation. The study's empirical data were collected through content analyses of relevant documents and interviews with actors who participated in the evaluation processes. The results indicate that the underlying drivers of rationality are mainly visible during the initial phase and the ongoing dialogue between the actors. It also emerges that the logic of consequences and the logic of appropriateness are empirically close to each other in terms of visible views on rationality, which makes the understanding of rationality in the processes subjective and sometimes it's difficult to separate the theories on an empirical level. In the material, there are varying degrees of support for both logics in different parts of the process. Overall, the different logics are not necessarily mutually exclusive.