There has been little research into poetry classification and the potential to access poems by form and genre. The categories listed in the Library of Congress Genre/Form Terms (LCGFT), Wikipedia, Amazon.com, and the poetry-sharing platform, PoetrySoup, were compared through a systematic mapping process. It was found that LCGFT coverage is more extensive for poetry than fiction, but all four sources’ coverage is limited. Beyond a small core of well-established forms and genres, poetry is classified in many less well-known ways, with many categories based on form, as well as a wide range of other characteristics, including some very specific ones.