Solid Phase Extraction (SPE) has become a powerful and extensively used technique in the clean-up and concentration of samples in a wide variety of analytical techniques. This volume explains the principles behind SPE and provides protocols to help readers master extraction problems. These detailed methods are particularly suited to solving extraction problems in forensic, pharmaceutical, and clinical chemistry and include readily understandable explanations of the principals of pH, ion exchange, and co-polymeric mechanism-enhanced SPE. Each protocol is described in step-by-step detail and contains an introduction outlining the principle behind the technique, a list of equipment and reagents, troubleshooting advice, and tips on how to avoid known pitfalls.