East-West Management Institute's Open Development Initiative is a network of open data platforms that span five countries in the Lower Mekong Region. Open Development Cambodia (ODC) is the initiative’s flagship site, and aims to offer open source data aggregated across sector and industry in Cambodia; an innovative service to the users of its platform and a first for the country. The SIPA workshop team was enlisted to perform an impact assessment of the ODC platform and how it is used by development actors in the region. Through a combination of in-person stakeholder interviews and an online survey, the SIPA team identified key performance indicators along three broad categories; activity metrics, quality metrics, and impact metrics. Additionally, the workshop team provided recommendations for improving ODC’s scope and reach through both a proposed theory of change and methods to improve outreach.