This paper reviews and compares folk theories and empirical evidence about the influence of parenthood on happiness and life satisfaction. The review of attitudes toward parenthood and childlessness reveals that people tend to believe that parenthood is central to a meaningful and fulfilling life, and that the lives of childless people are emptier, less rewarding, and lonelier, than the lives of parents. Most cross-sectional and longitudinal evidence suggest, however, that people are better off without having children. It is mainly children living at home that interfere with well-being, particularly among women, singles, lower socioeconomic strata, and people residing in less pronatalist societies--especially when these characteristics are combined. The discrepancy between beliefs and findings is discussed in relation to the various costs of parenting; the advantages of childlessness; adaptation and compensation among involuntarily childless persons; cognitive biases; and the possibility that parenthood confers rewards in terms of meaning rather than happiness.