Coronary angiography continues to be the standard for assessing coronary artery obstructive disease. Coronary angiography is used not only in diagnosis, but also to assess the appropriateness and feasibility of various forms of therapy. In addition, information provided by coronary angiography is useful for assessing prognosis in patients with coronary artery disease. It helps to decide, whether percutaneous coronary angioplasty, coronary bypass surgery or medical treatment should be performed. Bypass surgery has been shown to improve prognosis in patients with left main and three vessel disease. However, in patients with single vessel disease, choice of therapy generally does not influence prognosis. Although the overall risk of coronary angiography is very low, it should be restricted to patients in whom the information obtained is expected to improve management.