Preventing the transmission of African trypanosomes between mammalian hosts has been one of the most effective mechanisms to date for the control of these important parasites. Hence, understanding the mechanisms through which they control their life cycle in molecular terms could provide valuable strategies for restricting the impact of sleeping sickness. Over the past two to three years, the study of the molecular cell biology of trypanosome life cycle progression has made considerable advances. Here, these advances are placed in the context of the biology of the parasite, to provide an integrated overview of developmental events in Trypanosoma brucei.