Microarray technology provides a highly sensitive and precise technique for obtaining information from biological samples, with the added advantage that it can handle a large number of samples simultaneously that may be rapidly analyzed. The protocols collected in this important volume provide instruction in designing and constructing DNA arrays as well as hybridizing them with biological sample for analysis. Opening with an overview from Professor Southern on the history of DNA array technology, the reader is provided with an all-encompassing manual of the latest state-of-the-art techniques including descriptions of unique ways to synthesize arrays using the photolithographic approach, the synthesis and use of modified monomers, genotyping using DNA Mass Array methodology, as well as information on antisense reagents, a future drug market that will be used to study the effects of these molecules by using array hybridization. Also covered are the business aspects of biochip technology as well as the ethical issues related to genetic analysis. Comprehensive and state-of-the-art, this book will be useful to all levels of scientists from novices to those intimately familiar with array technology.