Here's a list of 50 essential books of poetry that pretty much everyone should read. There's something for everybody here, from the deeply established canonical works to riveting, important books by newer poets, from the Romantics to the post-modernists, from the goofy to the staid. NB: as with other lists like these, only one work per author has been included, and there is a bias against the "Collected Poems of" unless necessary. Obviously, inevitably, painfully, there are many, many poets and works of poetry, both of great renown and less so, that are missing here and should still be read by everyone.
