Housed in something that looks vaguely like a square gray envelope that's guaranteed to wear out if you're not careful, this album is still one of the only places to locate many of Parker's best 1958-1966 Duke sides (unless you've got the 45s salted away somewhere). "Man or Mouse," "Dangerous Woman," the two-part "These Kind of Blues," and "I'll Forget About You" are prime vehicles for Parker's uncommonly smooth vocals and occasional harp blasts.