The authors examined perceived internal and external barriers to postsecondary educational plans among 140 Mexican American and 296 White high school students, attending to sex, socioeconomic, ethnic differences. Parent education was associated with educational plans. Girls anticipated encountering more barriers associated with financing postsecondary education than their male counterparts. Mexican American students anticipated encountering more postsecondary education barriers associated with ability, preparation, motivation, support, and separation, and expected those barriers to be more difficult to overcome, than their White counterparts. Implications for research and practice are discussed. (Contains 3 tables.)