We test core theories of the household using variants of a public good game and experimental data from 240 couples in rural Uganda. Spouses do not maximise surplus from cooperation and realise a greater surplus when women are in charge. This violates assumptions of unitary and cooperative models. When women control the common account, they receive less than when men control it; this contradicts standard bargaining models. Women contribute less than men and are rewarded more generously by men than vice versa. This casts doubt on postulates in Sen (1990). While the absence of altruism is rejected, we find evidence for opportunism. The results are put in a socioeconomic context using quantitative and qualitative survey data. Assortative matching and correlates of bargaining power influence behaviour within the experiments. Our findings suggest that a .one-size fits all. model of the household is unlikely to be satisfactory.