Studies have shown that neighborhood conditions and experiences may individually or collectively impact health. Using 38 years of longitudinal data from the Panel Study of Income Dynamics (PSID), we clarify the relationship between child and adult neighborhood quality and self-reported adult health, using sibling fixed effects models. Overall, we find support for positive long-term health effects, both for growing up in affluent neighborhoods and for growing up in neighborhoods where one is surrounded by comparative advantage. Relative to childhood neighborhood factors, adult neighborhoods have little to no effect in almost every model specification. We find mixed evidence, as well, that these relationships are stronger for nonwhites than for whites. Our findings suggest that childhood is a critical point for intervention in the long-term health effects of residential conditions.