The authors determined whether the cognitive processes that underlie second-language acquisition difficulties are the same as those that underlie reading difficulties. First-grade (N = 101) bilingual and nonbilingual children were administered a battery of measures in Spanish and English. English word identification and vocabulary were predicted by a language-general working-memory (WM) factor, whereas English pseudoword reading was predicted by Spanish pseudoword reading and WM. The results also showed that (a) children proficient in language were better able to access resources from WM and (b) children with reading disabilities (RD) performed poorly on Spanish measures of short-term memory. In general, second-language difficulties are related to accessing a language-independent WM system, whereas language-specific phonological memory deficits underlie RD.