This paper sets out to provide empirical evidence on the existence of imperfections in the capital markets in the Spanish case, and their repercussions in the taking of investment decisions on the part of com-panies. To that end, a panel of Spanish companies has been constructed on the basis of data provided by the Central de Balances del Banco de España. The results point to the existence of behaviour which can be differentiated as between companies in function of their financial situa-tion (internal resources), which is consistent with the existence of im-perfections in the capital markets.

Keywords: investment and the financing of companies, imperfect capital markets.