Throughout their marriage, Sylvia Plath and Ted Hughes engaged in a complex and continually evolving poetic dialogue about writing, love, and grief. Although scholars have commented extensively on the biographical details of Plath's and Hughes's marriage, few have undertaken a systematic intertextual analysis of the poets' work. The Grief of Influence reappraises this extraordinary literary partnership, and shows that the aesthetic and ideological similarities that provided a foundation for Plath's and Hughes's creative marriage - such as their mutual fascination with D. H. Lawrence and motifs of violence and war - intensified their artistic rivalry. Through close readings of both poets' work and analysis of new archival sources, Clark reveals for the first time how extensively Plath borrowed from Hughes and Hughes borrowed from Plath. She also explores the transatlantic dynamics of Plath's and Hughes's 'colonial' marriage within the context of the 1950s Anglo-American poetry scene and demonstrates how each poet's misreadings of the other contributed to the damaging stereotypes that now dominate the Plath-Hughes mythology. Following Plath and Hughes through alternating periods of collaboration and competition, The Grief of Influence shows how each poet forged a voice both through and against the other's, and offers a new assessment of the twentieth century's most important poetic partnership.