Geoffrey Hill is a poet who writes mainly in the form of poetic sequences. This thesis examines Hill's sequences to illuminate his poetic career, especially the proliferation of published poetry in the last twenty years of his life. The introduction defines 'sequence' and offers a taxonomy of the forty-five sequences in Broken Hierarchies. The first chapter examines 'Metamorphoses' in terms of generic ambiguity. The second discusses 'Of Commerce and Society' as variation and disrelation. Chapter 3 explores the forms of Hill's sequences from the 1960s and 1970s in terms of what he, following Hopkins, calls 'the monumentality/bidding nexus'. It examines 'Funeral Music' as processional; 'The Songbook of Sebastian Arrurruz' as implicit moral drama; Mercian Hymns as his first book-length sequence; 'The Pentecost Castle' as song cycle; 'Lachrimae' as dance; and 'An Apology for the Revival of Christian Architecture in England' as historical imaginary. Chapter 4 studies the book-length sequences from the middle phase of Hill's career - The Triumph of Love; Speech! Speech!; The Orchards of Syon; and Scenes from Comus - with respect to extension, epanorthosis, relationality, and multimodality. It argues that the sequence-form allows Hill to incorporate shortcomings of the self; to stage character comedy; and mix modes in ways which prevent any single mode from dominating. This emboldens him to include laus et vituperatio, the confessional, and the farcical, along with polemical interventions in 'culture wars'. Chapter 5 explores the aesthetics of dissonance and how sequence represents selfhood and time, over a long-term project: Hymns to Our Lady of Chartres, 1982-2012. The final chapter discusses Hill's early models of sequence; notes mid-length sequences in Canaan, Without Title, and A Treatise of Civil Power; suggests that sequence releases Hill from the impasse of lyrical perfectionism; and sketches a critical approach to The Daybooks and The Book of Baruch.