Worlds Imagined: 14 Short Sci-fi is an anthology of science fiction short stories and novels edited by Robert Silverberg and Martin H. Greenberg. Originally published in 1989, it includes works by famous authors such as Isaac Asimov, Robert A. Heinlein, and James Tiptree Jr.   
 
Editors: Robert Silverberg and Martin H. Greenberg
Original publication date: January 13, 1989
Notable stories included:
"The Dead Past" by Isaac Asimov
"By His Bootstraps" by Robert A. Heinlein
"Houston, Houston, Do You Read?" by James Tiptree Jr.
"A Case of Conscience" by James Blish
"The Star Pit" by Samuel R. Delany
"Born with the Dead" by Robert Silverberg
"On the Storm Planet" by Cordwainer Smith
"The Golden Helix" by Theodore Sturgeon
"The Road to the Sea" by Arthur C. Clarke
"Dio" by Damon Knight