The United Nations established Sustainable Development Goal 6, universal access to safely managed drinking water and sanitation service, as a global goal for 2030. In rural areas, access lags significantly and progress is rarely examined concurrently between developed and developing nations. Therefore, this dissertation focuses on rural water system challenges in a developed nation, the US, and a developing nation, Guatemala. In the US, approximately 250 million Americans receive drinking water from community water systems (CWSs), theoretically safeguarded by the Safe Drinking Water Act (SDWA). There is mounting evidence that racial, ethnic, and socioeconomic disparities persist in US drinking water access and quality, but studies are limited by the exclusion of very small CWSs and a large geographic unit of analysis. A novel geospatial methodology was created to delineate system service areas at the zip code scale in Virginia and assess the influence of demographic characteristics on compliance with the SDWA from 2006 to 2016. Results reveal that monitoring and reporting violations are concentrated in private, rural systems that serve fewer than 500 people, while health-based violations were more likely in non-white communities, specifically those with higher proportions of Black, Native Hawaiian, and other Pacific Islanders. This study was completed in parallel with a household sampling campaign in rural San Rafael Las Flores, Guatemala. In Guatemala, no public access to water system compliance or quality information currently exists. With growing investment in mining industries and recognized naturally occurring arsenic in volcanic geology, citizens are eager for drinking water information. Survey results highlighted dissatisfaction with and distrust in most tap water sources. Consequently, residents regularly buy bottled water or collect water from untreated natural springs. Water quality results indicated that tap water from the central drinking water treatment plant contained higher levels of arsenic and other contaminants, when compared to most other sources. Though the settings are quite different, parallel investigation of rural drinking water system challenges in the US and Guatemala reveal common challenges and lessons. Moving forward, all nations would benefit from standard monitoring of drinking water access, quality, and compliance that allowed for intersectional investigations of environmental health inequities. / Doctor of Philosophy / In 2015, the United Nations established Sustainable Development Goal 6 which establishes safely managed drinking water and sanitation service for all as a global goal. Access to safe drinking water lags significantly in rural areas and can be complicated by intersecting social determinants of health (e.g. race, wealth). Rarely is progress in developed and developing nations examined concurrently, hindering an understanding of commonalities and an exchange of lessons. To this end, my dissertation focuses on rural water system challenges in a developed nation, the United States, and a developing nation, Guatemala. In the US, more than 250 million Americans receive in-home drinking water from one of 53,000 community water systems, with quality theoretically protected by the Safe Drinking Water Act (SDWA). Recent failures, such as the lead crisis in Flint, MI, have cast doubt on the equity and reliability of these utilities, especially in underserved areas. How can we ensure that all US communities receive equal protections under the Safe Drinking Water Act? Using publicly available data and geography, this work estimated service areas to determine whether SDWA violations related to surrounding community socio-demographics and/or system design. Results reveal that monitoring and reporting violations are significantly concentrated in private, rural systems that serve fewer than 500 people, while health-based violations were more likely in non-white communities, specifically those with higher proportions of Black, Native Hawaiian, and other Pacific Islanders. These findings illustrate potential issues of environmental justice within VA and advocate for future research to investigate potential structural causes. This work was completed in tandem with a household sampling campaign in rural San Rafael Las Flores, Guatemala. In Guatemala, there is currently no public access to water system compliance or quality information. With recognized naturally occurring carcinogenic elements in Guatemala's volcanic geology, such as arsenic, and heightened investment in extractive industries such as mining, that can compromise source water quality, citizens are eager for drinking water quality data. Survey results documented widespread dissatisfaction with and distrust in tap water quality. As a consequence, residents regularly buy bottled water or collect water from natural springs. Water quality results showed that tap water sourced from the central drinking water treatment plant contained significantly higher levels of arsenic and other contaminants when compared to most other tap sources. Community participation in long-term water monitoring and infrastructure decisions may help build trust in water sources. Though the regulatory, economic, and cultural settings are quite different, parallel investigation of rural drinking water system challenges in the US and Guatemala reveal common challenges and lessons. Moving forward, high, middle, and low-income nations all benefit from standard monitoring of drinking water access, quality, and compliance that allows for intersectional investigations of environmental health inequities.