Studies of membrane transporters have had great impact on our und- standing human diseases and the design of effective drugs. About 30% of current clinically marketed drugs are targeting membrane transporters or channels. Membrane Transporters: Methods and Protocols provides various practical methodologies for the ongoing research on membrane transporters. To provide readers the most up-to-date information, several emerging fields and methodologies are embraced in this book, including pharmacogenomics, bioin-formatics, and microarray technology. Pharmacogenomics studies of membrane transporters are useful in drug discovery and in predicting drug responses in the clinic. In this volume, the current status of pharma- genomics studies of transporters is reviewed and research methodologies in this field are described. Transporter classification is important in studying the structure and function of membrane transporters and has thus triggered intensive interest in recent years. Membrane Transporters: Methods and Protocols provides a systematic classification of all transmembrane transport proteins found in living org- isms on Earth. This classification system will be helpful for further studies on various aspects of membrane transporters, especially for such large-scale gene expression studies as those employing microarray technologies. Bioinformatics is frequently used in transporter studies and has become indispensable for all kinds of research methods. Commonly used bio- formatics methods, such as databases and tools for sequence analysis and - tif studies, are explained in order to facilitate membrane transporters research. Because of heterogeneous sources and tremendous amounts of data, data in- gration has become one of the most important issues in transporter studies.