Instrumentation (2 players): 5 timpani, trombone. “In and Out” is a true duet, with both instruments participating equally in the musical dialogue. The piece begins with a thunderous fanfare of call-and-response motives between the timpani and trombone, followed by a short section that features both instruments in lyrical passages. Alternating between 4/4 and 3/4, the next section quickens in pace with both instruments taking on the role of melody and counter-melody at different times. The tempo continues to build in each major section, with the initial call-and-response returning at the end of this four-minute duet. The timpani part can be played on five drums of standard sizes, but a few quick changes in the first section would be easier with six drums (an additional 23- or 26-inch drum). Tuning changes are straightforward, but not notated. Short, fun, and a little challenging, this piece is very appropriate for two intermediate players new to chamber music playing.