Global scaling up rural sanitation is aWater and Sanitation Program (WSP) project currently beingimplemented in India, Indonesia, and Tanzania. Working withlocal governments and the private sector in 29 districts ofEast Java province in Indonesia, WSP's approachcombines generating demand from local governments prior toinitiating project interventions and demand from consumersfor improved sanitation facilities and behaviors prior tomaking a greater range of sanitation products and servicesavailable through local markets. This demand responsiveapproach combines Community-Led Total Sanitation (CLTS),behavior change communication, and sanitation marketingapproaches to help villages become open defecation free(ODF). At the end of the third year of projectimplementation, household access to sanitation is growing atrates hitherto never seen in rural sanitation projects inIndonesia. On average, one-third of all triggeredcommunities have become ODF within a year. However, acrossdistricts, varying levels of progress have been achieveddepending on the extent of political support garnered,implementation capacity developed, and thecost-effectiveness of interventions undertaken. However,during 2009 the project team observed that while monitoringdata was being generated regularly in the communities, muchof this data was not reaching sub-district, district, orhigher levels for regular consolidation. With the number oftriggered communities running into the thousands in EastJava, it had become too labor and time intensive forgovernment outreach staff to collect data manually from eachtriggered community on a monthly basis. In response to thischallenge, a community-based participatory outcomemonitoring system was developed.