Household production constitutes an important aspect of economic activity and ignoring it may lead to incorrect inferences about levels and changes in well-being. This paper sheds light on the importance of unpaid work by making use of detailed time-use surveys for 25 OECD member countries and 3 emerging economies. The calculations suggest that between one-third and half of all valuable economic activity in the countries under consideration is not accounted for in the traditional measures of well-being, such as GDP per capita. In all countries, women do more of such work than men, although to some degree balanced – by an amount varying across countries – by the fact that they do less market work. While unpaid work – and especially the gender division of unpaid work – is to some extent related to a country’s development level, country cross-sectional data suggest that demographic factors and public policies tend to exercise a much larger impact. The regular collection of time-use data can thus be of tremendous value for government agencies to monitor and design public policies, and give a more balanced view of well-being across different societies.