This study is about conception in the evaluation of financial assistance within the social services. The aim of this study is to describe and understand how social workers reason about variation, conception and local norms and its significance in the evaluation process. To reach this purpose we have conducted semi-structured interviews with eight social workers in which different themes were discussed and reasoned about. In order to understand and analyze our results we have studied/used the knowledge about tacit knowledge and street-level bureaucracy. Our results showed, as previous research states, that social workers do have conceptions about clients. Beyond that it also showed that they were well aware of the presence of the conception and that it is consistently processed with the help of colleagues. In addition to the help of colleagues the use of self-reflection was valuable to increase the awareness about conception. Furthermore the study showed that social workers believe that the conceptions are established through ones qualities and experiences. Social workers also suggest that these two variables contribute to their gut feeling, which they mean to be inevitable in the evaluation process. The study concluded that there is an ongoing reasoning about conception in the evaluation process of financial assistance among social workers and that social workers found it to be important to continuously discuss and deal with this issue.