Housing costs are critical determinants of the living conditions of individuals and households. The main indicator of housing costs used below is the share of household income that is devoted to housing, based on data from the annual national accounts of OECD countries. Housing expenditures of households, as defined in national accounts, include actual and imputed rents (the rent-equivalent that home owners would pay for a house with similar characteristics to the one the own), spending on housing maintenance and repairs, as well as the costs for water, electricity, gas and other fuels. They exclude the interest and repayments on loans for home purchases as inclusion of these alongside imputed rents would amount to double counting. Imputed rents are a better measure of “true” housing costs, as some part of mortgage repayments should really be seen as household savings. Because of the long delays in data collection and dissemination, national account data on housing costs presented here only extend to 2003 for most countries.