[en] This Revision 9 of the fourth edition of the NRC Staff Practice and Procedure Digest contains a digest of a number of Commission, Atomic Safety and Licensing Appeal Board, and Atomic Safety and Licensing Board decisions issued during the period from July 1, 1972 to September 30, 1987 interpreting the NRC's Rules of Practice in 10 CFR Part 2. This Revision 9 replaces in part earlier editions and supplements and includes appropriate changes reflecting the amendments to the Rules of Practice effective through September 30, 1987. The Digest is roughly structured in accordance with the chronological sequence of the nuclear facility licensing process as set forth in Appendix A to 10 CFR Part 2. Those decisions which did not fit into that structure are dealt with in a section on ''general matters.'' Where appropriate, particular decisions are indexed under more than one heading. Some topical headings contain no decisions citations or discussion. It is anticipated that future updates to the Digest will utilize these headings