Cardiology remains predominantly a clinical specialty and there is no substitute from obtaining an adequate story of the presenting problem from the patient. However, despite this, partly through advances in technology, we have available many useful diagnostic tests, most of which are extremely safe and non invasive. There is no doubt that these have taken some of the guess work out of managing our patients and has therefore lead to better outcomes in nearly all aspect of Cardiology. These tests are discussed here to help patients understand what is involved with them.