OBJECTIVE: To compare recent trends in smoking initiation by adolescents with trends in inflation-adjusted cigarette pricing and tobacco marketing expenditures. DESIGN: We examined smoking initiation trends in demographic subgroups of adolescents aged 14-17 years during the decade 1979-1989. Data on cigarette pricing and tobacco marketing expenditures were adjusted for inflation and plotted over this same period. SETTING: Large population surveys, United States. SUBJECTS: 140,975 ever-smokers aged 17-38 when surveyed in 1992 or 1993, who reported on age of smoking initiation during the decade 1979-1989. MAIN OUTCOME MEASURE: Initiation rate was calculated as the number in an age group who reported starting to smoke regularly in a year, divided by the number of never-smokers at the start of the year. Trends were evaluated by linear and quadratic models. RESULTS: From 1979 to 1984, adolescent initiation rates decreased, but increased thereafter, particularly among males, whites, and those who, as adults, reported never having graduated from high school. Cigarette price increased throughout the decade as did tobacco marketing expenditures, especially for coupons, value-added items, and promotional allowances. CONCLUSION: Availability of cheaper cigarettes is not likely to be a cause of increased smoking initiation by adolescents. Although other influences cannot be ruled out, we suspect that the expanded tobacco marketing budget, with its increased emphasis on tactics that may be particularly pertinent to young people, affected adolescent initiation rates.