The main of this study is the analysis of the behaviour of Portuguese households’ demand and saving, with the help ol Extended Linear Expenditure System and Almost Ideal Demand System. Our purpose is ti find detailed elements about households’ motivation to consume or save , about the structure of households’ consumption and about the way socioeconomic and demographic variables influence that expenditure. Studies in this field have proved to be quite important, since they allow the analysis of the consumer’s attitude, which is one of the conditioning features of the implementation of economic politics.

keywords: Extended Linear Expenditure System, Almost Ideal Demand Sustem, Elasticity, Subsistence Expenditure.