School readiness is important for children, for their families, and for society at large. The authors' exploration of school readiness focuses on how the home literacy environment, parenting behavior, and social characteristics affect two aspects of school readiness: basic skills, such as reading and math; and behavior problems, including sad/anxious behavior and aggressive behavior. The discussion is based on information drawn from the Los Angeles Family and Neighborhood Survey (L.A.FANS), a survey of 65 neighborhoods in Los Angeles County conducted in 2000-2001. The analysis shows that mothers' educational attainment and neighborhood poverty are the two social characteristics most strongly associated with school readiness. In addition, ethnicity and immigrant status themselves are not important predictors of school readiness, once differences in socioeconomic status are taken into account. In fact, children whose parents were born outside the United States do better on basic skills than kids with U.S.-born parents when socioeconomic status is taken into account. The findings provide a clear picture of the factors that affect school readiness, and how the study results may be useful to individuals and groups involved in formulating programs to improve school readiness. Because resources for school-readiness programs are limited, it is particularly important to focus these resources on the children who need them most. The study suggests that the children most in need are those whose mothers are poorly educated and those children living in poor neighborhoods. (Contains 48 endnotes, 19 figures and 13 tables.) [Funding for this report was provided by the First 5 LA-RAND Research Partnership.]