The Jean Starr Untermeyer collection contains over 3,000 letters to Jean Starr Untermeyer and in some cases to Louis Untermeyer from a list of distinguished people; Jean Starr Untermeyer's letters; Louis Untermeyer's letters; various manuscripts for individual poems and prose works by Jean Starr Untermeyer and Louis Untermeyer; typescripts; various auxiliary manuscripts by other authors; photographs; and miscellaneous peripheral items.