Walk on the Wild Side: The Best Horror Stories of Karl Edward Wagner, Volume 2 - Karl Edward Wagner, Stephen Jones, J.K. Potter, Laird Barron, Peter Straub An incredible collection of Wagner's later works, bearing witness to the pain that would cut short his career and his life. These stories all bear the scars of the battle between his personal demons and his muse, including several which are painfully autobiographical, giving the reader an unflinching view into the psyche of a man at his breaking point. Featuring an introduction and an afterword by friends remembering the last times they saw him, this volume is a fitting memorial to one of the true masters of his generation. Highly recommended.

Just wanted to add that Laird Barron did not write the afterword in this volume. David Drake did.
Laird wrote the afterword in Where the Summer Ends: The Best Horror Stories of Karl Edward Wagner, Volume 1