This longitudinal study documents the key role of early joint engagement in the language and early literacy development of Mexican-American children from low-income households. This rapidly growing population often faces challenges as sequential Spanish-English language learners. Videos of 121 mothers and their 2.5-year-old children interacting in Spanish for 15 min were recorded in 2009-2011 in the Dallas-Fort Worth metropolitan area. Researchers reliably rated general dyadic features of joint engagement-symbol-infused joint engagement, shared routines and rituals, and fluency and connectedness-that have been found to facilitate language development in young English-speaking children. The construct respeto, a valued aspect of traditional Latino parenting, was also rated using two culturally specific items-the parent's calm authority and the child's affiliative obedience. In addition, three individual contributions-maternal sensitivity, quality of maternal language input, and quality of child language production-were assessed. General features of joint engagement at 2.5 years predicted expressive and receptive language at 3.6 years and receptive language and early literacy at 7.3 years, accounting for unique variance over and above individual contributions at 2.5 years, with some effects being stronger in girls than boys. The level of culturally specific joint engagement did not alter predictions made by general features of joint engagement. These findings highlight the importance of the quality of early communication for language and literacy success of Mexican-American children from low-income households and demonstrate that culturally specific aspects of early interactions can align well with general features of joint engagement.