Though references to ritornello form in Baroque music are commonplace, the literature lacks a consistent accounting of what that form is, or even exactly what the term "ritornello" means musically. Jason Yust writes that ritornello "refers to a return of material that may occur in multiple keys" (Yust 2018, 270). However, William Caplin (1998, 243) focuses on the alternation of solo and tutti textures rather than material, suggesting a strict association between ritornello form and concertos (as do most textbooks). This paper presents a methodology that adopts a more flexible definition of ritornello form that accommodates movements featuring an alternation of solo and tutti textures as well as those that do not. It then applies this methodology to the twenty-two ritornello form movements found in Handel's Op. 6 (1739-40) set of twelve concertos and discusses what that application reveals.