This Updated 4th Edition revises the casebook to account for the restyling of the Federal Rules of Civil Procedure. The pagination has not changed from the 4th Edition (2005). Students will be alerted to the new numbering and wording of the Rules; but teachers can continue to use their current versions of the 4th edition as originally published. On December 1, 2007, the "restyled" Federal Rules went into effect. The hope is that this restyling will pay dividends for decades, and that beginning law students will be among the first beneficiaries. For them, the restyled rules will be the only rules they will know in their professional careers. We assume that most teachers will have their students read and learn from the restyled rules. But this watershed does not change what's in the decided cases under the rules as they were written before Dec. 1, 2007. So students may find it unnerving for their rule pamphlets to say something different from what they find quoted in the cases in the casebook. The Updated 4th Edition is designed to deal with these issues. It has been changed only to reflect changes in numbering or wording of the rules that resulted from the restyling project. Teachers who have been using the 4th edition as published in 2005 can continue to use it; they need not start working afresh with the updated 4th edition. To facilitate that continued use of the existing book, we will soon circulate a listing of the changes in this revised edition. Teachers will therefore be able simply to annotate their copies of the original 4th edition and have the equivalent of what the students possess in the updated 4th edition. In addition, the authors have added an Appendix including two post-publication decisions that were previously handled by circulating edited versions suitable for class handouts--Bell Atlantic Corp. v. Twombly and Exxon Mobil Corp. v. Allapattah Services, Inc. The authors have included footnotes on the pages where they recommend substituting these cases to refer readers to them. In 2009, we expect to publish the 5th edition. That will, of course, be based on the restyled rules, but it move far beyond the minimal accounting for small numbering and wording changes resulting from restyling. We are pleased to announce that Professor James Pfander, of Northwestern University Law School, will be a new co-author on the 5th edition.