Interventions to prevent tobacco sales to minors have been largely unsuccessful in affecting adolescent smoking behavior. A systematic review of the evidence by Stead and Lancaster (2000) included controlled studies, with and without random assignment, carried out in a variety of populations. Based on this review of published interventions, Stead and Lancaster concluded that regular enforcement of retailer behavior and, in some cases, simple retailer education, can successfully increase retailer compliance with the law. In these same studies, however, there was little impact on adolescents' perceived ease of access to tobacco or, most importantly, on their smoking behavior (see, e.g., Altman, et al., 1999; Rigotti, et al., 1997). Researchers have posited several possible reasons for this finding. Without complete compliance, a means of access to tobacco will remain (Stead & Lancaster, 2000), and adolescents may learn which stores are willing to sell to them or may buy tobacco in other communities with lesser enforcement (Rigotti, et al., 1997). Furthermore, retailer compliance is measured through compliance checks with test buyers, but these tests may not accurately measure adolescents' ease of access to tobacco. Actual underage buyers may differ from test buyers in lying about their age, using a fake ID, having an older individual buy tobacco for them, or being familiar to the vendor (Stead & Lancaster, 2000; Altman, et al., 1999; Rigotti, et al., 1997). Moreover, many adolescents obtain tobacco by means other than purchase in a store (Robinson, et al., 1998).