This paper evaluates the additionality of a Clean Development Mechanism (CDM) bagasse cogeneration project at Kakira Sugar Works (KSW) in Uganda using what the author refer to as an ex-post comparative baseline approach that accounts for how background economic conditions and project financing evolved over the project’s seven year crediting period from 2008-2014. The CDM is found to have accelerated the capacity of KSW to reduce emissions associated with Uganda’s national grid, but not at the rate claimed in the CDM project documents — only about one-third of carbon credits claimed under the CDM were found genuine. The conditions of additionality can change significantly over the course of a CDM project in a way that undermines project environmental integrity because the CDM rules do not accommodate changing baseline conditions.