Abstract This chapter aims to discuss some distinguishing syntactic and interpretative properties of German causal weil-clauses, da-clauses and verb-first causal clauses. The chapter argues that these different properties can be fruitfully analysed in Krifka’s (2018, to appear) system of decomposition of a speech act into the levels of a proposition, of a judgement, of a commitment and of a speech act. These semantic levels are represented in syntax by TP, JP, ComP and ActP, respectively. Standardly, a weil-clause is just a TP (covered by a CP-shell). In contrast, a da-clause is of the more complex category JP (covered by a CP-shell), which is adjoined to the JP of its host, i.e., a da-clause is interconnected with a judgement. Related to this there are, for example, the findings that in contrast to the situation with a weil-clause, a da-clause cannot be narrowly focal, that the causal relation expressed by da is not at-issue, and that there is no binding from the host into a da-clause. Furthermore, a da-clause may host a certain type of root phenomena. A verb-first causal clause is of the most complex category ActP and is licensed by an ActP. It cannot be syntactically embedded and it has illocutionary force, which, however, has a supporting function with regard to the illocutionary force of the preceding sentence. A verb-first causal clause may host all kinds of root phenomena. The chapter also compares Krifka’s layers of interpretation and Sweetser’s (1990) three domains of interpretation (content, epistemic, speech act) and shows that these two classifications complement each other with correlations.