The paper studies the demand for international tourism, in the Mediterranean region. First a review of the most important attempts to model econometrically the demand for international tourism in the past is given, followed by a formal presentation of the proposed theoretical model. In particular, a version of the Almost Ideal Demand System (AIDS) is adopted and a description of the variables involved and their sources, together with the estimation procedure, are provided. The diagrammatic analysis performed contributes to a better understanding of the evolution of the dependent variable over time. The results with respect to the expenditure as well as to the own- and cross-price elasticities may be regarded as econometrically satisfactory and a reasonable economic explanation is given.