The Best of James H. Schmitz was published in 1991 by NESFA and is described in the NESFA Press on-line catalog . Also, the
Linkoping Sci-Fi archives contain a review
of the book.
Stories in The Best of James H. Schmitz :
Mischief in the Spaceways (intro by Janet Kagan)
Grandpa
Lion Loose...
Just Curious
The Second Night of Summer
Novice
Balanced Ecology
The Custodians
Sour Note on Palayata
Goblin Night
Bibliography (from the Whole Science Fiction Database
Illustrations by Merle Insinga