Professor of economics at Oxford University, Paul Collier believes that profit gained from resource extraction will trump all other sources of income for the continent in the foreseeable future. "But, too often in Africa’s history," he says, "money that should have financed productive investment has been looted or squandered. The challenge now is to prevent the continent’s sad history of exploitation from repeating itself during the coming era of massive resource extraction. Whether natural resources are plundered or harnessed for development depends upon several factors..."