Gregory is a member of the Board of Advisors and lecturer for the NSA-certified University of WashingtonCertificate in Information Security and Risk Management, and on the Board of Advisors and the lead instructor for the University of Washington Certificate in Information Systems Security. He is also a member of the board of directors of the Evergreen State chapter of InfraGard, and a founding member of the Pacific CISO Forum.

As an InfraGard member, Gregory served as an expert witness in the 2006 cybercrime case, United States vs.Christopher Maxwell.

• Gregory, Peter. Solaris Security, Prentice-Hall, 1999. ISBN 0-130-96053-5
• Gregory, Peter. Solaris Security (Japanese Language Edition), Prentice-Hall, 1999. ISBN 4-881-35974-6
• Gregory, Peter. Solaris Security (Chinese Language Edition), Prentice-Hall, 1999. ISBN 7-115-08728-8
• Gregory, Peter. Sun Certified System Administrator for Solaris 8 Study Guide, Prentice-Hall, 2001. ISBN 0-130-40933-2
• Gregory, Peter. Enterprise Information Security, Financial Times Management, 2003. ISBN 0-273-66157-4
• Gregory, Peter. Enterprise Information Security (Romanian Language Edition), Financial Times Management, 2003. ISBN 973-722-043-9
• Gregory, Peter; Miller, Lawrence. CISSP for Dummies, John Wiley & Sons, 2003. ISBN 0-764-51670-1
• Gregory, Peter; Miller, Lawrence. Security+ Certification for Dummies, John Wiley & Sons, 2003. ISBN 0-764-52576-X
• Gregory, Peter. Computer Viruses for Dummies, John Wiley & Sons, 2004. ISBN 0-764-57418-3
• Gregory, Peter; Simon, Mike. Blocking Spam and Spyware for Dummies, John Wiley & Sons, 2005. ISBN 0-764-57591-0
• Gregory, Peter. VoIP Security for Dummies, Avaya Limited Edition, John Wiley & Sons, 2006. ISBN 0-764-03744-X
• Gregory, Peter. SIP Communications for Dummies, Avaya Limited Edition, John Wiley & Sons, 2006. ISBN 0-470-04149-8
• Gregory, Peter. Converged Network Security for Dummies, Avaya Limited Edition, John Wiley & Sons, 2007. ISBN 0-470-12098-9
• Gregory, Peter. IP Multimedia Subsystems for Dummies, Radisys Limited Edition, John Wiley & Sons, 2007. ISBN 0-470-13587-7
• Gregory, Peter. Midsized Communications Solutions for Dummies, Avaya Limited Edition, John Wiley & Sons, 2007. ISBN 0-470-16552-2
• Gregory, Peter. Comunicaciones para Medianas Empresas para Dummies, Edicion Limitada de Avaya, John Wiley & Sons, 2007. ISBN 978-0-470-27666-2
• Gregory, Peter. Unified Communications for Dummies, Avaya Limited Edition, John Wiley & Sons, 2007. ISBN 0-470-17495-1
• Gregory, Peter. Comunicações Unificadas, Edicao Espeçial da Avaya, John Wiley & Sons, 2007. ISBN 978-0-470-27690-7
• Gregory, Peter. Securing the Vista Environment, O'Reilly Media, 2007. ISBN 0-596-51430-1
• Gregory, Peter; Miller, Lawrence. CISSP for Dummies, Second Edition, John Wiley & Sons, 2007. ISBN 0-470-12426-1
• Gregory, Peter. IT Disaster Recovery Planning for Dummies, John Wiley & Sons, 2007. ISBN 0-470-03973-6
• Gregory, Peter; Simon, Mike. Biometrics for Dummies, John Wiley & Sons, 2008. ISBN 0-470-29288-1
• Gregory, Peter. Data Backup for Dummies, EVault Special Edition, John Wiley & Sons, 2008. ISBN 0-470-40662-5
• Gregory, Peter; Miller, Lawrence. SIP Communications For Dummies, Avaya 2nd Custom Edition, John Wiley & Sons, 2009. ISBN 978-0-470-38114-4
• Gregory, Peter. CISSP Guide to Security Essentials, Thomson Course Technology, 2009. ISBN 1-435-42819-6
• Gregory, Peter. CISA Certified Information Systems Auditor All-in-One Exam Guide, McGraw-Hill Osborne Media, 2009. ISBN 0-071-48755-7
• Gregory, Peter; Miller, Lawrence. CISSP for Dummies, Third Edition, John Wiley & Sons, 2009. ISBN 0-470-53791-4

Gregory has written several articles for Computerworld and Software Magazine including:

• Protect Apps and Data with a Disaster Recovery Plan
• Identify Vulnerabilities with Application Scanning Tools
• Integrity begins within: Security pros lead by example
• Vulnerability Management Ushers an Era of Technical Risk Management
• Security in the software development life cycle
• Tipping sacred cows: Make bold decisions to protect your information
• Lessons learned from the blaster worm
• For an infosecurity career, get the technical basics first

Gregory has been interviewed by trade publications including Information Security Magazine, CIO Magazine, and Computerworld.