Open Budget Survey (OBS) is a global research initiative conducted biennially by the International Budget Partnership (IBP). Its purpose is to independently measure government budget transparency, public participation, and the strength of legislative and audit bodies in their oversight roles. First launched in 2006, the OBS is the world's only independent, comparative, and fact-based research instrument of its kind. Currently, the survey is conducted in around 125 countries, with Tanzania being among them, having participated in nine rounds of the OBS from 2006 to 2023.