The Kirby 23 sailboat was designed by Bruce Kirby and saw limited production circa 1985-1986. The hull from the very successful Sonar was modified to produce the Kirby 23 to enable it to complete in PHRF and Midget Ocean Racing Club (MORC) regattas. Basic modifications include the following; a galley, head, larger cabin, life lines, increased sail area, and increased rudder surface area. The boat has a PHRF rating around 178 which makes it competitive with other boats of the era such as the J/22, J/24, and S2 7.9 models.