This topic includes: Classification of sanitation systems, On-site sanitation system , Off-site sanitation system, Basic principles and features, Suitability of sanitation system, Global context of water access, Hygienic latrine, Types of on-site sanitation (Pit latrine and Pour flush latrine), Advantages and disadvantages of simple pit latrine, Water seal in pour flush latrine, Direct pit, Offset pit and Twin pit pour flush latrine, Advantages and disadvantages of pour flush latrine, Construction of pit, Septic tank, Fecal Sludge Management System (emptying, collection, transportation, treatment and disposal), Drying bed and composting of sludge