- Papyri and Ostraka Collection (23)
- Paritosh Collection of Donald Clay Johnson (1057)
- Paul U. Kellogg Papers (9)
- Penumbra Theatre Company Records (525)
- Penumbra Theatre Playbills (72)
- Performing Arts Archives General Collection (15)
- Performing Arts Publications Collection (2)
- Philosophical Psychology Lectures (12)
- Photochrom Collection (13)
- Photographic Lab Collection (UMD) (2064)
- Pioneer and Endicott Buildings Collection (83)
- Polish American Collection (183)
- Portraying Memories - Portraits & Conversations Survivors of the Shoah (9)
- Postcard Collection (251)
- Pre-Modern East Asian History of Medicine Texts (151)
- PubH 3040 Dying and Death in Contemporary Society (6)
- Pulp Novel Covers (54)
