Circle of Friends, by Rick Robertson, is a two-volume collection containing a total of 24 character pieces for piano in each of the major and minor keys (minus enharmonic equivalents), in a manner similar to the Prelude sets by Chopin, Rachmaninoff, and the like. The sequence as published is arranged in a rough order of difficulty, allowing for convenience in page turns here and there.
The title alludes as well to the familiar “Circle of Keys’. As for “friends”, each piece is dedicated to a close friend, colleague, or student. A few pieces in Volume One are at the early intermediate level, while Volume Two is solidly at the intermediate level with a steady trajectory of more demanding musical concepts.