This paper examines how much of the dispersion in economic performance across OECD countries can be accounted for by economic geography factors. More specifically, two aspects of economic geography are examined, namely the proximity to areas of dense economic activity and endowments in natural resources. To do so, various indicators of distance to markets, transportation costs, and dependence on natural resources are added as determinants in an augmented Solow model, which serves as a benchmark. Three measures of distance to markets are found to have a statistically significant effect on GDP per capita: the sum of bilateral distances, market potential and the weighted sum of market access and supplier access. And the estimated economic impact is far from negligible. The reduced access to markets relative to the OECD average could contribute negatively to GDP per capita by as much as 10% in Australia and New Zealand. Conversely, a favourable impact of around 6-7% of GDP is found in the case of two centrally-located countries: Belgium and the Netherlands. Endowments in natural resources are also found to have a significant positive effect on GDP per capita, suggesting that OECD countries have, on average, escaped the natural resource curse or severe forms of the Dutch disease. The paper provides also some tentative evidence that spending on R&D and human capital might have a stronger effect on GDP per capita in countries with a higher degree of urban concentration.