Books about Human-alien encounters -- Fiction (sorted alphabetically)
- Peacemaker Alan Edward Nourse
- Pen Pal Stephen Marlowe
- Perfect Answer Jr. L. J. Stecher
- Peril of the Blue World Robert Abernathy
- Peril of the Starmen Kris Neville
- Pictures Don't Lie Katherine MacLean
- Pilot and the Bushman Sylvia Jacobs
- Piper in the Woods Philip K. Dick
- Plagiarist From Rigel IV Evan Hunter
- Planet for Your Thoughts James Norman
- Planet Named Joe Evan Hunter
- Planet of Doom Stephen Marlowe
- Planet of No-Return Wilbur S. Peacock
- Planet of Sand Murray Leinster
- Planet of the Damned Harry Harrison
- Planet of the Gods Robert Moore Williams
- Planet That Time Forgot Donald A. Wollheim
- Plotters Richard S. Shaver
- Pogo Planet Donald A. Wollheim
- Polite People of Pudibundia R. A. Lafferty
- Poors Harry Lorayne
- Prelude to Space Robert W. Haseltine
- price of eggs Randall Garrett
- prince of space Jack Williamson
- Prison Planet Wilson Tucker