Language and self-regulation develop bidirectionally, and they synergistically affect most aspects of acquiring reading proficiency. Children and youth from historically marginalized communities tend to have less expansive knowledge of academic vocabulary and dialect common to instruction and academic text (i.e., General American English), and limited self-regulation skills relevant to reading, compared to lessmarginalized peers. In this article, we argue that language and self-regulation are factors in demographicrelated reading opportunity gaps, and that in addition to improving students' access to high-quality explicit phonics instruction, understanding their interactive relationship offers opportunities for schools to reduce disparities in reading outcomes. Impact and ImplicationsLearning to read is a challenging process for most children, however, children from historically marginalized communities are more likely to enter school with less familiarity of language common to instruction and text, and limited self-regulation skills important for reading acquisition, than lessmarginalized peers. These knowledge and skills gaps are bidirectionally related and sources of demographic-related disparities in reading achievement, but represent critical opportunities to reduce inequities across the span of reading development.