Goal: Educators believe that parents can help their children learn to read. But what evidence supports this belief? And if parent involvement does matter, what kinds of parent involvement are most efficient? The goal of this report was to review the scientific literature on parent involvement in the acquisition of reading from kindergarten to grade 3. Method: In the present review, parent involvement in literacy acquisition was narrowly defined to include parent-child activities that focus on reading. Moreover, the 14 studies that were analyzed were those that included an intervention where researchers tested whether parent involvement enhanced children's literacy. Standard meta-analytic procedures were used to analyze the study outcomes. Findings: Overall: The combined results for the 14 intervention studies, representing 1174 families, were clear: Parent involvement has a positive impact on children's reading acquisition. The mean effect size for the combined studies was moderately large (effect size = .68). This effect size corresponds to a 10-point gain on a literacy test (with a standard deviation of 15) for the intervention children as compared to the control children. Findings: Intervention type: The three types of parent involvement represented in the review differed in their effectiveness. Having parents teach specific literacy skills to their children was two times more effective than having parents listen to their children read and six times more effective than encouraging parents to read to their children. In the present review, providing supportive feedback to parents during the intervention did not alter effectiveness. Also, the duration of the intervention did not moderate its effectiveness. Findings: Participant characteristics: Parent involvement had a positive impact from kindergarten to grade 3. In addition, the interventions were as effective for children experiencing reading difficulties as they were for normally-developing children. Finally, the socioeconomic level of the participating families did not affect the positive impact of the interventions. Findings: Study design: Studies that included standardized tests yielded smaller effects than other studies. Conclusion: Parents can help their children learn to read. The effectiveness of parents' help, however, varies according to the type of parent-child activities. Educators, when deciding which type of intervention to implement, will have to weigh the differences in effectiveness across the different types of intervention against the amount of resources needed to implement the interventions. Includes appendix of Statistical Formulas. (Contains 4 tables.)