Purpose: Early language intervention is essential for children with indicators of language delay. Enhanced milieu teaching (EMT) is a naturalistic intervention that supports the language development of children with emerging language. We conducted a systematic review and meta-analysis of all qualifying single-case and group design studies that evaluate the experimental effects of EMT on child outcomes. Method: We evaluated the risk of bias in the included studies and conducted a descriptive analysis of study quality, effect sizes, and demographics. We reviewed a total of 29 single-case and 17 group design studies in which 1,590 children participated. Results: Out of 46 studies, 39 met the What Works Clearinghouse standards without reservations, showing low levels of risk of bias. The effects were comparable when EMT was implemented alone and when it was implemented with another intervention component, and EMT was more effective when implemented by caregivers than when implemented by therapists. Most studies did not report sufficient participant demographics. Conclusions: The EMT research literature published thus far is of high study quality; the effects across studies are comparable; and the intervention has been studied via a wide range of delivery modalities, contexts, implementers, and samples. Future research could systematically examine the effects of EMT and explore these varying intervention delivery, implementer, and learner characteristics as moderators.