Let's commence with a prediction--within a year or two Lawrence Block will move out of the mystery-writer ghetto and, like such prior escapees as John D. MacDonald and Elmore Leonard, settle in the mainstream neighborhood, where sales are impressively larger and the sun shines all the livelong day.

Our prediction is based on certain clues. For instance, his novels have been getting better and better, earning him an increasing number of favorable reviews and a wider audience. Another, and equally important, clue is this present collection. Your run-of-the-mill mystery writer, one for whom his publisher has no great expectations, doesn't have his mystery and detective short stories issued between hard covers. Although this is a good book, he probably wouldn't have gotten it if Arbor House didn't have faith in Block and his future.

Block has a knack, probably based somewhere in his genes, for building an effective story out of a simple, original situation. He knows how to let things grow and develop naturally. This is especially evident in the title story, which has Matt Scudder, Manhattan-based hero of many of Block's novels, working to solve the murder of a bag lady. The woman, whom Scudder barely knows, has left him a small bequest and that draws him into the case. As it does the reader. A tough, realistic story, yet quietly so. It just seems to unfold as you read. Equally good are "With a Smile for the Ending," about a dying author who comes to think of his neighbors as characters in his books and the unfortunate consequences thereof, and "Leo Youngdahl, R.I.P.," a quiet story that can't be summed up easily. You have to read it.

Anyone who's read Block's Burglar novels (e.g. "The Burglar Who Painted Like Mondrian") knows he possesses a pretty fair sense of humor. That shows up in several of these stories, especially in "Death of the Mallory Queen." A brand new yarn, it features Leo Haig and Chip Harrison, the poor man's Nero Wolfe and Archie Goodwin. Besides being funny, this is a roman a clef, chock-full of thinly veiled New York mystery writers, editors and bookshop proprietors. I was also amused by, and this may indicate some serious flaw in my mental makeup, the two accounts of the activities of the dapper little lawyer named Martin Ehrengraf. Ehrengraf contends that none of his clients is ever guilty and he will, apparently, do anything, up to and including murder, to see to it not one of them is ever convicted. Looked on rationally these are mean-minded and nasty tales. I chuckled quite a bit while reading them.

My only disappointment was with a handful of the 20 stories, notably "Click!" and "Weekend Guests," in which Block resorts to using prefabricated plots. The clicks I heard in "Click!" weren't from the cameras being used but from the pieces of the mechanical structure falling predictably into place. Block always writes well, but even good prose can't disguise predictable situations.

All in all, though, a worthwhile compilation. And, when you start noticing Block's name up near the top of the best-seller lists, remember -- you heard it here first. The reviewer writes science fiction, mysteries and essays. His most recent novel is "The Prisoner of Blackwood Castle."