This report is the fourth update of a Water and Sanitation for Health (WASH) report on access to water and sanitation facilities in Central America. in the last 12 years, water coverage in Central America has risen from 56% to 63%, while sanitation coverage has risen from 42% to 67%. These increases represent 6.6 million people who have gained access to water supplies and 11 million who have gained access to sanitation facilities. The progress is remarkable when viewed against the background of economic and political turmoil in the region. However, in spite of this progress, survey findings from three cities in the region present a more complicated picture in terms of health impact than the provision or absence of water and sanitation facilities would indicate. The coverage figures reported here for the urban areas could be inflated; evidence from the urban study suggests that those living in peri-urban areas were not counted. More important than the coverage figures, which are only indirect measures of health status, are the increased health risks caused by the contamination of the urban environment. The evidence from the urban survey suggests that environmental contamination is a health risk to urban populations, and that the risk will increase over the coming years as human, solid, and hazardous wastes concentrations increase in the air, water, and home environments. Therefore, despite improvements in the last 12 years, the health impact of deteriorating water sources and living conditions has and will continue to undermine any advances in the provision of water and sanitation services. The future of water and sanitation programming, particularly in urban areas, must be viewed within a broader environmental health context. (Author abstract)