This presentation summarizes a multi-agency impact evaluation of malaria interventions in mainland Tanzania from 1999 to present. It provides an overview of the evaluation, including the institutions and stakeholders involved, key indicators and data sources being used, and the evaluation design and timeline. Challenges discussed include linking intervention coverage trends to morbidity and mortality trends over time given changing policies and limited early data. The presentation concludes with lessons learned around the need for country ownership, complementary district-level analyses, and additional data sources.