The Nucleolus is divided into three parts: nucleolar structure and organization, the role of the nucleolus in ribosome biogenesis, and novel functions of the nucleolus.  Proteomics has shown that there are hundreds of proteins of unknown function in the nucleolus, which are likely to keep researchers busy for years.  In addition, the roles of many viral components in the nucleolus will continue to intrigue us, hopefully moving beyond the phenomenology that is now the case with many viral components in the nucleolus.  Even now, there is already evidence that we can take advantage of our knowledge of the nucleolus to develop therapeutic strategies, and this book hopes to help build the path to a new era of nucleolar translational medical research.