I got to know Ronald L. Caravan after I unexpectedly received a set of CDs displaying his artistry on clarinet and saxophone, and also reflecting his gifts as a composer. Being greatly impressed by his musical prowess on these discs led me to contact him. The fact that he is a brother in Christ provided a further foundation upon which to build a friendship, which led ultimately to the composition of this Sonata for Clarinet and Piano, the latest entry in my ongoing series of sonatas for every major orchestral instrument. Given that Caravan is known for his publications on advanced clarinet and saxophone techniques, including microtones and multiphonics, I decided to include some of these in the present work, which was written in 18 composition sessions between May 7, 2018 and July 3rd of the same year. Due to the stylistic breadth of Caravan's own compositions, I also elected to make this work polystylistic. The work comprises four brief movements, each of which has its own character, and each likewise based in part on a particular mathematical constant. Thus, the first movement, a spiky movement with many changes of meter, draws upon the first 13 numbers in the sequence of pi (3.141592653589...) for the groupings of the notes in the left hand of the piano part in measures 79 through 89. The second movement, a slow movement making the greatest use of quarter tones and multiphonics in this Sonata, represents the mathematical constant, e, (2.71828182845904...) drawing in measures 11–17 from its first 15 digits for groupings of notes in the clarinet part. The third movement comprises a whirlwind scherzo which flits in and out of tonality. The Euler-Mascheroni constant is drawn upon in this movement. The first 21 digits of the number (.5772156649015328606065120900824024...) are represented by the grouping of notes alternating between the right hand of the piano and the clarinet as they exchange the running 16th-note line in measures 72–88. In the following six measures, the right hand and clarinet are playing together, so the next six digits are denoted by the use of accents at the beginning of each sequence of notes. The final movement employs the Fibonacci series, used by numerous composers before me. This series is characterized by the fact that every number after the first two is the sum of the two preceding ones. Its first nine numbers are 1,1,2,3,5,8,13,21,34, and thus the piece is divided into nine sections, each with a number of measures corresponding to the Fibonacci sequence, and each ending with a small break. Additionally, the Fibonacci series is depicted through intervallic content, with the lowest note on the clarinet (concert D below middle C) representing 1, and each semitone above it being numbered. The first eight notes thus formed are D, D, E-flat, E, F-sharp, A, D, B-flat, and in inverse fashion, D, D, C-sharp, C, B-flat, G, D, F-sharp. This aggregate of eight pitches is used exclusively throughout the first six sections of the piece, giving them a rather modal sound. Beginning in the seventh section, however, all 12 pitches of the chromatic scale are employed, along with various styllistic shifts ranging from quasi-ragtime to subdued freely tonal sections. The Sonata ends with a flourish in both instruments.