The American Water Works Association's Distribution and Plant Operators Division, recognizing the problem of lost or non-revenue producing water and desiring to find solutions for member utilities, requested this committee report to be written. Many decision-makers in the water supply field are satisfied when they are accounting for 85% of the water which they produce. Due to increasing demands for water, coupled with higher operational costs, this report recommends that lost or non-revenue producing water should be less than 10%, and recommends certain guidelines which should be followed when it does not.