Marketplace practices are integral to the larger economic and social context of adolescent health risk behaviors. To corporations and marketers, adolescents represent a gold mine of current and future profits. Adolescent incomes increased by almost a third in the 1990s. The annual spending of the U.S. adolescent population is estimated now to have reached 155 billion US dollars. The sheer size of the adolescent population and its spending power are of keen interest to corporations and marketers. This chapter presents a brief history of youth-targeted marketing and examines the major avenues in the media and inside schools that marketers and corporations use today to reach adolescents with their messages and products. It outlines the impact of consumerism and marketing on adolescent health using five case examples: tobacco, alcohol, cosmetic surgery, laxatives, and diet pills. It then concludes with a discussion of resistance efforts, led by health advocates, policy makers, parents, and youth themselves to restrict sales of harmful products to youth and curtail advertisers' access to adolescents in schools. A critical role for adolescent health researchers and advocates is to contribute a public health perspective into ongoing debates over regulating business practices that negatively affect the health of young people.