This article focuses on the functions and the meaning potential of Swedish det-constructions, i.e. constructions with the non-referential pronoun det as subject. The aim is to show how the constructions construe meaning through verbs and participant roles and how they can be used to express assessment through modality. Moreover, the distribution of non-referential det and referential det is investigated in three text types. The material consists of det-clauses in academic works, news reports and personal blogs. The results show that referential and non-referential det have about the same frequency in all the investigated text types. Active det-constructions are non-agentive and mostly non-dynamic, expressing states, while passive det-constructions are dynamic and implicate an Agent. However, the Agent role is not expressed in passive det-constructions, which suggests a lower degree of agentivity in comparison to passive constructions without det. The results also show that different det-constructions can be used as a modal resource expressing modal assessment by the matrix clause, which thus can be considered an alternative to modal adjuncts and verbs.