CISSP is a higher level certification that covers the ten domains of security and would be appropriate for an enterprise level security manager.
SSCP is more for the Network Security guru. Still covers the ten domains and such, just at a more technical level
Various other certs generally cover specific OS and network security.

So, much depends on your level in the org, and where you want to be/go?

Here's a good site for the CISSP/SSCP:

http://www.cissp.com/Exam/exam.html