"Fortunate Person" – see "The Luckiest Man in the World"
"Game: First Schematic" (1971?, Can You Feel Anything When I Do This?)
"George and the Boxes" (1995, Never published in English, first published in Polish; Russian translation published in Новые Миры Роберта Шекли, Vol. 2. Полярис, 1998)
"Operating Instructions" (1953, Astounding 1953/5, later in Beyond the Barriers of Time and Space anthology, ed. Merril, 1954)
"Pandora's Box – Open with Care" (2000, Uncanny Tales, F&SF 99/3)
"Paradise II" (1954, Notions: Unlimited)
"Pas de Trois of the Chef and the Waiter and the Customer" (1971, Can You Feel Anything When I Do This?)
"Pilgrimage to Earth" (1956, Pilgrimage to Earth. Also known as "Love, Inc.")
"Plague Circuit" (Can You Feel Anything When I Do This?)
"A Plague of Unicorns" (1995, Peter S. Beagle's Immortal Unicorn, Vol. 2, co-edited with Peter S. Beagle; with help from Martin H. Greenberg. HarperPrism, Hardcover, October 1995)
"Potential" (1953, Shards of Space)
"Primordial Follies" (1998, Ma che Pianeta mi hai Fatto?, only published in translation to Italian)
"Privilege of Age" (2003, BIGNews (also on Internet) 2003/3)