Public health practitioners increasingly agree that it is not enough to provide people with water and sanitation hardware. Numerous approaches are used to tackle the "software" which means to ensure behavior change necessary to come along with the sanitation hardware. A review of these approaches reveals several shortcomings, most importantly that they do not provide behavioral change interventions which correspond to psychological factors to be changed. This article presents a sound psychological model, which postulates that for the formation of new habitual behavior, five blocks of factors must be positive with regard to the new behavior: risk factors, attitudinal factors, normative factors, ability factors, and self-regulation factors. Standardized tools for measuring the factors in face-to-face interviews are presented, and behavioral interventions are provided for each factor block. A statistical analysis method is presented, which allows the determination of the improvement potential of each factor.