Good water, sanitation, and hygiene (WASH) services protect health and the environment. Such services are particularly important in schools to instill lifelong proper hygiene habits in children and provide them access to the requisite facilities. Many schools in Mongolia face significant challenges in improving WASH due to physical and demographic conditions. The country's harsh winters require sustainable WASH facilities that can withstand extended periods of below-freezing temperatures. This publication provides essential information for national and local administrators, engineers, field practitioners, and policy makers to plan, implement, and manage improved WASH in schools, particularly in small and isolated rural settlements. It covers WASH standards and norms, design and technology options, operation and maintenance, hygiene education approaches, and cost estimation.