Last month's presentation `Linux Firewalls' focussed on keeping your internal network free from unwelcome Internet visitors. This month Matthew Feldt, chair of the Linux SIG, will discuss internal Unix security issues and describe some of the popular Unix security tools available on the Internet designed to keep your system secure. Due to a large number of requests, some time will be devoted to describing installation and usage of Phil Zimmerman's PGP (Pretty Good Privacy) encryption program.