Purpose: This article describes and reports the results of testing a new conception of how leadership influences student learning ("The Four Paths"). Framework: Leadership influence is conceptualized as flowing along four paths (Rational, Emotions, Organizational, and Family) toward student learning. Each path is populated by multiple variables with more or less powerful effects on student learning. Leaders increase student learning by improving the condition or status of selected variables on the Paths. Research Methods: Evidence includes teacher responses to an online survey (1,445 responses) measuring distributed leadership practices in their schools (N = 199) and variables mediating leaders' effects on students. Grade 3 and 6 math and literacy achievement data were provided by the province's annual testing program. The 2006 Canadian Census data provided a composite measure of school socioeconomic status. Path modeling techniques were used to test six hypotheses. Results: The Four Paths model as a whole explains 43% of the variation in student achievement. Variables on the Rational, Emotions, and Family Paths explain similarly significant amounts of that variation. Variables on the Organizational Path were unrelated to student achievement. Leadership had its greatest influence on the Organizational Path and least influence on the Family Path. Implications: School leaders and leadership researchers should be guided much more directly by existing evidence about school, classroom, and family variables with powerful effects on student learning as they make their school improvement and research design decisions. (Contains 2 figures, 2 tables and 12 notes.)