While Ginsberg was certainly influenced by earlier generations of writers stretching back to the Metaphysical Poets, contemporary writers were also instrumental in helping him craft his own poetic vision. Foremost among them was his friend Jack Kerouac, who became a source of inspiration, guidance, and mentorship for Ginsberg throughout his life. This chapter explores the twenty-five years of profound yet tumultuous relationship that developed between the two writers, from their encounter in New York City in 1944 to Kerouac’s death in 1969. While their passionate and sometimes turbulent friendship sparked Ginsberg’s creative energy, Ginsberg drew heavily on Kerouac’s themes and stylistics – including his writing method of “spontaneous prose” – which became central to his own poetical voice. Though their relationship eventually fractured in the 1960s owing to political differences and rivalry, Kerouac continued to play a crucial role in shaping Ginsberg’s growth both as a writer and as an individual.