Funders, donors, and non-profit agencies are striving to demonstrate impact. However, each looks to different data sources and uses different tools to learn whether impact is being achieved. The effort to collect, analyze and report on an ever growing amount of information is costly and confusing, leading to frustration at funder and agency levels. To demonstrate accountability, understand the collective impact of effort, and learn what works, some funders and agencies are developing common indicators or shared measurement approaches to evaluate impact. In the 20th century, this approach was conducted using a top-down or bottom-up process. A 21st century development is an omni-directional process. This session will describe two projects, one international and one US based, where funders and agencies have worked collaboratively to develop shared measurement and reporting systems. This path is exciting but not without peril. Panel members will discuss the benefits and costs of this participatory approach.