With some of the worst poverty statistics in Africa, Zambia appears to have little to show for a century of mining. But given good policies, the countrys considerable mineral wealth clearly represents a real opportunity to grow the economy and tackle poverty. Following the recovery of the mining industry since privatisation, and with booming world copper prices, there has been considerable public debate over how to ensure that an appropriate share of mineral resource revenues accrues to the government. Debate is healthy and should lead to better policy, but only if it is well informed. While technical terms such as windfall tax are frequently used by participants in the debate, there is no common understanding of the term. The full-?length guide upon which this brief is based has been written to address this information gap and to inform one of the most important debates in Zambia.