This paper analyzes the firm characteristics which are determinants of capi
tal structure according to different explanatory theories, and how institut
ional characteristics affect capital structure. We have developed a target
adjustment model, which has then been confirmed by our empirical evidence.
It highlights the fact that the transaction costs borne by Spanish firms ar
e inferior to those borne by US firms. Our results are consistent with tax
and financial distress theories and with the interdependence between invest
ment and financing decisions; they also provide additional evidence on the
pecking order and free cash flow theories. Finally, the evidence obtained c
onfirms the impact of some institutional characteristics on capital structu
re. (C) 2001 Elsevier Science B.V. All rights reserved.