This study examined how early writing develops in Spanish-English-speaking children of Mexican and Central American descent who are dual language learners (DLLs) in the United States. The emergent writing skills in Spanish and English of 140 preschoolers in a multisite study were assessed using name- and word-writing tasks during the children's prekindergarten year. A subset of children were assessed in Kindergarten. Findings suggest that Spanish-English DLLs exhibit a similar progression in their conceptualization of writing to monolingual preschool-aged children, progressing from universal to language-specific writing features. Similarities in the development of the conceptualization of the writing systems specific to each of their languages were also observed. Strong cross-linguistic association between writing words in English and Spanish from fall to spring was found in the children's earlier phases of writing conceptualization. Vocabulary skills also seem to influence their writing development after phonological analysis skills have emerged.