Readers of James Merrill’s poetry have long noted affinities and contrasts between Merrill and Yeats. This Composite Voice is the first in-depth examination of the extensive history and particularly vexed nature of this lifelong poetic relationship. It draws on little-known biographical material, uncollected poems, manuscript variants, and annotations found in Merrill’s copies of Yeats poems, essays, and A Vision , as well as a close examination of Merrill’s better-known writing, to establish the many ways in which Merrill contends with the older poet’s haunting personality and poetic accomplishment. It shows how Merrill repeatedly turned to Yeats, not only in his poetry, but also a a guide in matter amorous and occult, and concludes by showing how Merrill works to over-master the ‘master-critic’ by incorporating Harold Bloom’s theories of poetic influence into the subject matter and structure of his most ambitious poem, The Changing Light at Sandover .