Included here are letters received by O'Neill and his responses. These are more focused on issues and legislation, with accompanying background material occasionally attached. "Dear Colleague" correspondence, through which legislative support was sought by and solicited from O'Neill, is filed here. Such solicitations come not only from congressional colleagues but also from corporate executives and constituent organizations.

Collection is open for research. Selected items are closed due to fragility; a microfilm access copy is available. Audiovisual recordings in this collection have been migrated from source media; digital use copies can only be accessed onsite in the Burns Library Reading Room.