John W. Keating reviews the principles of VAR analysis with particular emphasis on two structural VAR approaches. The two approaches impose restrictions on contemporaneous and long-run behavior to identify a structural model from the reduced form. The author provides empirical examples with a standard group of macroeconomic variables to illustrate these two approaches. The empirical long-run structural model yields results that are generally consistent with the theoretical model, whereas the results for the contemporaneous model are frequently inconsistent with theory. These findings suggest that long-run structural VAR models are superior; however, additional investigation should determine whether this result is robust or simply a special case.