Book excerpt: There is a significant gap in current knowledge about infusion therapy for treating different pain, headache and psychiatric conditions. Infusion therapy is now a common practice but there is considerable variation in how the therapy is implemented in different centers which can be both dangerous, if high doses are given, or ineffective, if low doses are given. This book provides a practical guide to infusion therapy for clinicians on how to safely and effectively perform this kind of therapy. Chapters cover the pharmacology of each medication and evidence in literature regarding indications, contraindications and doses. A recommended algorithm is provided for patient selection, doses, infusion technique/doses and appropriate monitoring. Infusion Therapy is the first comprehensive, clinical guide to this practice and is an invaluable resource for clinicians in anesthesia, pain medicine, internal medicine and palliative care. It will also be of interest to researchers and pharmacologists who would like to find out how clinicians use infusions.