This book traces the development of Marianne Moore's poetry throughout her sixty-year career as one of America's finest poets. Margaret Holley examines changes in Moore's approach to moral and artistic values, and discusses how language and form were distinctive in each of the poet's major phases. The study shows how the solitary, satirical voice of Moore's early verses matured into the wise observer of the later, major poems. Holley demonstrates how the virtuoso work of the middle years, infused with compassion and a sense of community, relaxed into the playful meditations of Moore's old age, when fame had brought her wide readership and acclaim. In exploring how shifts in Moore's poetic voice reflected important stages of her overall poetic growth, Holley provides detailed readings of the poems. The poetic strategies examined include: Moore's deployment of emblems and mottoes, her blend of overt and covert quotation, changes in her metaphoric language, her use of model stanzas in syllabic verse, her preferences for rhyme and closure, and her distinct spatial imagination.