Coronary intervention may be combined with diagnostic cardiac catheterization or performed separately. In the early years of angioplasty, performing these procedures separately was standard practice. Gradually, ad hoc intervention (performing diagnostic angiography and coronary intervention within the same session) has become more common, largely because of its convenience for patients and efficiency for physicians. However, the safety and potential cost savings of this approach remain uncertain. Criteria for the appropriate use of ad hoc intervention have not been established. Ad hoc intervention is reasonable for many, but not appropriate for all patients and should not be considered standard therapy. This document updates an earlier review of this topic and provides suggestions for the use of ad hoc intervention as a routine strategy.