Human African trypanosomiasis, better known as sleeping sickness, nowadays ranks among the more neglected diseases in the countries of Africa where it is found. Though it still kills many people every year, it cannot compete for celebrity with such major killers as malaria and AIDS. Yet that was not always the case. A hundred years ago, sleeping sickness attracted considerable scientific research and political attention because of its importance to the conquest of sub-Saharan Africa by the European colonial powers.