The picture is all too common. In fact, you probably see it in about 1 of every 10 patients who come through your door. The runny nose, scratchy throat, itchy eyes, recurrent sneezing, and annoying cough all point to an allergy. But where do you start and how far do you go in your search for the cause? In this article, Dr Volcheck describes the most commonly used tests for detecting sensitivity to specific IgE allergens and discusses the clinical usefulness and practicality of the various diagnostic procedures.