This article presents evidence for sex-specific temporal associations between major cigarette marketing campaigns and increases in youth smoking initiation using national survey data for 1910-1977 (N = 165,876). Considerable smoking initiation occurred in males under 18 and born before 1890 when marketing focused only on males. Initiation in male youth increased greatly during 1910-1919; in 1912, R.J. Reynolds launched its unprecedented campaign for Camel brand. Initiation in female youth began in the mid-1920s, coincident with the Chesterfield and Lucky Strike women's marketing campaigns. In the late 1960s, smoking uptake among young females again increased rapidly, coincident with large-scale marketing of women's brands. Male initiation did not increase with these campaigns. Thus, in each instance, major marketing impact occurred in youth smoking initiation only in the sex group targeted.