This chapter discusses the sonnet as a context for Hopkins’s poetry. It traces the history of the form and observes the nature of its popularity in the nineteenth century, noting the influence particularly of Milton and Wordsworth. Ideas about the generative potential of restricted poetic forms shape Hopkins’s experimentation with the sonnet. The chapter closes by asserting that while Hopkins’s innovative approach to the sonnet is clear, he found richest expression not so much by explicit departures from received poetic forms as he did within and through those forms.