William Webbe's A Discourse of English Poetry (1586) is the first printed treatise exclusively dedicated to devising a canon for the definition of poetry in England. Traditionally eclipsed by the academic centrality of Philip Sidney's The Defence of Poesy (c. 1580; published 1595) and George Puttenham's The Art of English Poesy (1589), this is the first critical edition of the essay in over a hundred years. This volume presents a modern-spelling text and a critical apparatus derived from the collation of the first printed document with subsequent editions. The explanatory notes incorporate recent research on Elizabethan literary theory and aim at substantiating Webbe's contribution within the academic and literary spheres of sixteenth-century England. A Discourse offers an enlightening testimony of the main concerns of Tudor humanism, and it also sheds light on the ideological foundations of the acclaimed quantitative reformation of metre launched by Sidney, Harvey, Spenser and other contemporary scholars.