IN REACHING SOLUTIONS FOR THE PLAN AND DESIGN OF WATER SUPPLY SYSTEMS FOR RURAL AREAS OF DEVELOPING COUNTRIES, PREFERENCE MUST BE GIVEN TO SYSTEMS WHICH TRY TO USE LOCALLY AVAILABLE LABOR AND MATERIALS AND TECHNICAL SYSTEMS AND TREATMENT METHODS WITH FEW AND EASILY RENEWABLE ACCESSORIES AND SELF-MADE CHEMICALS. THIS DISCUSSION OF FACTORS TO CONSIDER IN PLANNING AND DESIGNING SUCH PLANTS ALSO INCLUDES DETAILED REFERENCES WHICH ARE PART OF THE STUDY TITLED "TREATMENT METHODS FOR WATER SUPPLIES IN RURAL AREAS OF DEVELOPING COUNTRIES." AN ANNEX WITH DIAGRAMS DESCRIBES 13 TYPES OF WATER RECOVERY, TREATMENT, OR DISTRIBUTION SYSTEMS.