One purpose of this report is to review the scientific basis for identification and delineation of wetlands as currently reflected in federal manuals and regulatory conventions. The report is intended to identify both strengths and weaknesses of current regulatory practice. The committee's charge also asks that we deal with the basis for translation of definitions into practical, scientifically valid methods to efficiently and consistently identify wetlands. The committee decided that the translation of a definition or of particular standards or criteria into practical methods is also dependent on certain principles of regulatory practice and thus Chapter 9 titled Regulation of Wetlands and other discussion pertaining to regulation of wetlands (e.g., review of Nationwide Permit 26 and functional assessment) is included in this report.