The Policy Research Working Paper Series disseminates the findings of work in progress to encourage the exchange of ideas about development issues. An objective of the series is to get the findings out quickly, even if the presentations are less than fully polished. The papers carry the names of the authors and should be cited accordingly. The findings, interpretations, and conclusions expressed in this paper are entirely those of the authors. They do not necessarily represent the views of the International Bank for Reconstruction and Development/World Bank and its affiliated organizations, or those of the Executive Directors of the World Bank or the governments they represent.

Large investments in road infrastructure continue to be high on the agenda of many African countries, only a few of which have actually amended their investment strategy. In many cases, there seems to be a preference for a status quo that can easily be explained by political-economy factors driving policies in the sector. After presenting data on the state of roads in subSaharan Africa (length, density, condition), this article demonstrates how most countries' transport strategies are based on certain misperceptions and recommends better prioritisation of investments, better procurement and contract management, better projects implementation and better monitoring to improve the developmental impact of recent road investments.

ECAM II) to analyse how road access affects labour activities. It shows that one-sizefits-all road investments are irrelevant because the effects of roads are neither systematic nor uniform: the impacts of isolation on household wellbeing through labour-market opportunities are heterogeneous and depend on local characteristics. In view of the diversification of activities in household strategy, it finds that better road access increases the number of activities within those households that are most isolated.