This collection contains: Something Up There Likes Me by Alfred Bester; Lecture Demonstration by Hal Clement; Earlybird by Theodore R. Cogswell and Theodore L. Thomas; Probability Zero: The Population Implosion by Theodore R. Cogswell; The Emperor's Fan by L. Sprague de Camp; Brothers by Gordon R. Dickson; Lodestar by Poul Anderson; Thiotimoline to the Stars by Isaac Asimov; Black Sheep Astray by Mack Reynolds; Epilog by Clifford D. Simak; Interlude by George O. Smith; Helix the Cat by Theodore Sturgeon; and The Mothballed Spaceship by Harry Harrison.