Structural genomics is certainly not limited to plants, let alone a single plant genus. We chose to focus on cotton for a couple of reasons. One, of course, is its usefulness as an agricultural product. For example, structural genomics may be able to explain why tetraploid cotton species have higher productivity and quality than their diploid relatives. Perhaps more importantly, though, we chose cotton because the individual species have traits that make them ideal for exploring and advancing a new technology in structural genomics. Cotton genomes are an excellent model for structural genomics. For example, there are living species today whose diploid genomes are very similar to the two genomes that first came together to make the tetraploid. That makes for some interesting comparisons between the tetraploid sub-genome and its diploid cousin. What is more, the two genomes that came together are related, but different sizes. That not only makes them easier to tell apart within the tetraploid, it also means there are interesting structural features to look for between the two genomes. Finally, cotton is a great model because for all the different species, there is a surprising amount of similarity. Many groups of related plants have genome sizes and compositions that vary greatly from species to species, but for one reason or another this is not the case in cotton. As different cotton species arose, their genomes stayed largely the same. This is intriguing for structural genomics, because it means that any differences that do exist between one species and another must be really significant.