Abstract
The application of genetic testing to predict how well or how poorly an individual will respond to a therapeutic drug is beginning to make its way into the clinical laboratory. As this testing begins to unfold in the clinical setting, there is a necessary paradigm change that must occur for the laboratory and for the healthcare provider in order for this to be successful. New molecular-based technologies are commercially available to perform this testing on a routine basis and several established examples of pharmacogenetic tests are currently being performed. Several national organizations are now working on practice guidelines for the incorporation of this testing into a clinical setting. This manuscript provides an overview of where we are with respect to pharmacogenetic testing.