Comparative Genomics, Volume 2, provides a collection of robust protocols for molecular biologists beginning to use comparative genomic analysis tools in a variety of areas. Volume 2 contains the last three of seven sections. In the second volume, the fifth section describes a number of tools for comparative analysis of domain and gene families. These tools are particularly useful for predicting protein function as well as potential protein-protein interactions. In the sixth section, methods for comparing groups of genes and gene order are discussed, as are several tools for analyzing genome evolution. Finally, the seventh section deals with experimental comparative genomics. This section includes methods for comparing gene copy number across an entire genome, comparative genomic hybridization, SNP analysis, as well as genome-wide mapping and typing systems for bacterial genomes. Given the tremendous increase in available biosequence data over the past ten years, Comparative Genomics, Volume 1, is timely, comprehensive, and novel. A companion Volume 1 is also available from Humana Press.