Children’s well-being around the age when they start school is crucial for their future success in the educational system. Factors in the first 3 years of a child’s life matter for the child’s well-being when he or she starts school. This article analyzes the relationship between early childhood factors–such as maternal employment, family structure, and family life–and future child well-being. The analysis uses the psychosocial SDQ-scale and the number of problems experienced around starting school as measures of well-being. Results show that family factors in particular are important, while the effect of maternal employment–if any–is positive. In addition, the results differ markedly between girls and boys.