Evaluates project to assist Foster Parents Plan International (PLAN) to construct wells and water supply/sanitation systems in the vicinity of Yogyakarta, Indonesia. Special evaluation covers the period l981-11/82 and is based on document review, site visits, and interviews with project staff and beneficiaries. PLAN has constructed 442 wells, 14 community gravity water systems, 7 water storage tanks, 689 latrines, and 42 public bathhouses. Indirectly, PLAN has assisted nonclient families by providing construction drawings and technical advice for water supply and sanitation systems. Some 14,500 families have been helped to improve or protect their water supply. Most surveyed beneficiaries reported that they now had more water than before (64%) and that the water was cleaner (78%) and easier to obtain (82%). The data, while weak, suggest that the wells have had greater impact on income in areas with long seasonal droughts and greater impact on health in areas with adequate year-round water supply. The PLAN project has been particularly strong in promoting community involvement; all activities are implemented by community members and wells tend to be used and maintained. Latrines are not used as much as they should be, however, especially in less densely populated areas, and community educational activities have been quite limited to date. Mindful of this, PLAN staff are developing training packages for water and sanitation and translating them into Javanese, and are also developing slide shows. From a technical perspective, water system planning was minimal, largely due to PLAN selection criteria and to staff limitations. Cracks were observed around one well apron, and one site lacked spring water storage, but most wells met construction standards and all 18 hand pumps were operational. Gravity water systems, however, had design deficiencies in their water treatment function and in their positioning, and rainfall catchment systems lacked directional control over runoff and were improperly used by villagers. There were no major bathhouse construction problems, but water from the bathhouses could be a potential health problem. Recommendations are made regarding planning, project management, education, community participation, and technical features.