This paper studies the fundamental characteristics of a subgroup of members of the family of complementary-contrastive discourse constructions in English. Following Ruiz de Mendoza and Gómez-González (2014) by discourse constructions this article refers to form-meaning pairings capturing relational meaning such as addition, exemplification, contrast, etc. grounded in high-level cognitive models. A discourse construction (e.g., X Let Alone Y; cf. Fillmore, Kay, & O’Connor, 1988), generally consists of a fixed part and two variables, where the fixed part is a connector (a discourse marker or a conjunction). The constructions under scrutiny indicate a relation between two elements or situations in the world that are opposites but not exclusive of each other. Many of the members of this constructional family have frequently been treated as fully interchangeable in standard lexicographic practice. By contrast, this paper argues that each of these constructions introduces small but decisive changes in focal structure, resulting in important differences in meaning. Taking this evidence into account, the paper specifies the cases where one construction is used with preference over the others.