A theoretical model in social psychology and family relationships that illustrates the changes in the emotional satisfaction of couples during married life using a curve reflecting the rise and fall of satisfaction. This model is based on the idea that marital satisfaction (see MARITAL SATISFACTION) is not static, but depends on the different stages of life, difficulties, achievements, and daily interactions of spouses. An analytical model that describes dynamic changes in marital satisfaction in the form of a curve reflecting periods of high and low satisfaction due to the influence of life stages, personal and social stressors, as well as the styles of interaction of spouses.