This seems like it should be fairly intuitive and I thought that this was already configured, but with this latest threat, I see that our SEPM is not configured properly. What I would like is to have the SEPM download onto the server the latest versions of the client. We would test the clients on a few systems and then push out to all client machines when testing is completed. I can see the LiveUpdate server policies, but that appears to allow the clients to individually go out to the Symantec site to download content. Our network guys frown on that. I have also seen this article, but that is a manual way of getting the latest version of the client AND SEPM. What did I miss? Thanks for your time.

The clients are not downloaded via the SEPM. They're alreaady setup when you install SEPM and if you upgrade. You can assign a package with autoupgrade.

See here:

How to upgrade Symantec Endpoint Protection clients using the auto-upgrade feature

You may need to disable the auto update , check this

Updating client software with a LiveUpdate Settings policy

http://www.symantec.com/business/support/index?page=content&id=HOWTO55485

Thank you for your replies. To be more clear, I have 12.1.2015.2015 installed on the SEPM. I have auto upgrade already configured as Brian posted. How do I go about upgrading the SEPM?

Following the link i metioned above for Obtaining the latest version of Symantec Endpoint Protection or Symantec Network Access Control, I got to the screen where I choose what it is I want to download. I selected Part 1 and Part 2, downloaded and then extracted the files. I am hesitant to proceed from there as I don't want to end up doing a complete reinstall on the SEPM. Will this just end up being an upgrade?

Part 1 contains EVERYTHING (client installs, SEPM, etc.). You just need to run the setup.exe under the SEPM folder and it will do the upgrade.

All relevant upgrade steps are here:

Upgrading or migrating to Symantec Endpoint Protection 12.1.4100.4126 (RU4 MP1)

This will clear you 

http://www.symantec.com/connect/articles/understanding-downloads-symantec-endpoint-protection-sep-121-available-symantec-fileconnect