The Let's Be Amigos bilingual education program served over 2,000 students in 12 schools in Philadelphia. Model A provided bilingual education to English- and Spanish-dominant pupils in prekindergarten through Grade 6. Model B provided bilingual instruction to Spanish-dominant pupils in kindergarten through Grade 5. The ARRIBA component provided bilingual instruction to Spanish-dominant immigrant pupils in Grades 4 through 12. The program was generally well managed. It received support from principals of schools in which it was conducted. The program was effective in enhancing reading and language arts competencies of Spanish-dominant pupils. Longitudinal analysis of the reading performance in English of Spanish-dominant elementary school pupils showed that there was more growth in this skill than was observed with previously used evaluation techniques. Testing of high school ARRIBA pupils' reading performance in Spanish showed that it was poor, probably because many had several years of all-English instruction prior to participating in Let's Be Amigos. The high school ARRIBA component clearly enhanced the probability that tenth-grade Hispanic pupils would graduate from high school three years later. English-dominant Model A pupils' reading competencies are substantial, with sixth-grade pupils performing at the third-grade rural Puerto Rican norms. (Author/CFM)