The "almost unknown" in the title of this collection refers to the fact that some of the songs, though never before published, have been recorded and might be known to the most knowledgeable of Sondheim connoisseurs. However, it is safe to say that the songs in this landmark collection are among the least known of Sondheim's creations. This book includes contents by show or film title as well as by song title, an introduction about Sondheim, a preface by the editor, and detailed notes about each work and the show it came from. The piano/vocal editions were all personally approved by Sondheim.