Former Afghan finance minister Ashraf Ghani is one of President Hamid Karzai’s most articulate and vociferous critics, and a chief contender against the incumbent in the upcoming August presidential election. A U.S.-educated former World Bank official, he quit Karzai’s cabinet in 2004, finding it corrupt, and has since then turned down “at least 100 offers” to rejoin Karzai’s team. Ghani, 60, talked to NEWSWEEK’S Ron Moreau and Sami Yousafzai in his comfortable house in suburban Kabul. Excerpts: