This paper develops an account of the German discourse particle denn that captures the meaning contribution of this particle in polar questions, wh-questions, and certain conditional antecedents in a unified way. It is shown that the behavior of denn exhibits an asymmetry between polar and wh-interrogatives, which can be captured by treating the particle as sensitive to the property highlighted by its containing clause, in the sense of Roelofsen and Farkas (Language 91(2):359–414, 2015). In addition, the paper argues that highlighting-sensitivity should be incorporated in the account of another discourse particle, German überhaupt, and discusses how the proposed account of discourse particle denn may be extended to also cover the use of denn as a causal conjunction.