My dissertation seeks to shed light on the emergence of the basic institutional structure of Sunni Islamic law by examining the role played by legal maxims--succinctly phrased general legal principles--in the formation of the four orthodox schools of legal thought between the ninth and eleventh centuries. The project is framed by the following key hypotheses: (l) the development of legal maxims by medieval Muslim jurists inaugurated a "meta-discourse" of abstract principles underpinning all of Islamic law; (2) the use of maxims in jurisprudence permitted the transformation of a collection of disparate and occasionally contradictory legal rulings into the structured, internally consistent canon constitutive of each school of law; (3) this harmonization of each school's juristic output enabled the consolidation of the four schools as stable, authoritative institutions. Drawing on more than forty previously unstudied manuscript sources located at repositories in Egypt, Turkey, Syria, and Ireland, my study will offer the first comprehensive historical overview of the hitherto nearly unknown field of legal maxims, begin to uncover the intellectual transformations that drove the evolution of Islamic jurisprudence in this formative period, and provide a conceptual vocabulary to enable comparative dialogue between scholars of Islamic law and other major legal traditions.