This novel analysis of the Imperative construction in English and Germanic, arguing for variation in the position of the subject within the clause, engages with key issues in syntactic theory - what is the motivation for displacement in natural language and how can it deal with the problem posed by attested cases of optional movement? The book engages in particular with the debate on whether movement is strictly triggered by morphsyntactic factors or whether it may also be motivated by interpretative considerations, given the central role of such interfaces in the minimalist framework.