This chapter outlines the issues that have dominated the research on double object constructions, focusing on the following questions: (i) what is the structure of double object constructions?, (ii) what is the relationship between the double object construction and its PP dative counterpart?, (iii) what are the constraints on double object constructions?, (iv) what is the crosslinguistic variation in the availability and the syntax of double object constructions? First, we review the major structures that have been proposed for double object constructions over the years. Next, we turn to the debate concerning what is referred to as the dative alternation; the alternation between double object constructions (e.g., John
gave Mary a book
) and their PP dative counterparts (e.g.,
John gave a book to Mary
). The biggest source of debate here is whether the two are transformationally related or not, with meaning differences and the productivity of the alternation playing a big role in the debate. We then turn to the constraints that double object constructions are subject to, focusing on passive movement, A‐bar extraction asymmetries, and scope. We conclude by examining the crosslinguistic variation in the availability of double object constructions.