AIX – System Logs

We have been advised by our auditors to collect and retain AIX syslogs. Is this a normal practice that is being done,(like the event log in NT, which is a lot easier to read and archive), and if so, what is your recommended size for the log, spacewise. How does one get to the syslog, as a secadmin, to view it. Is a script needed to archive the syslog on a regular basis?
Thanx for all your info.