Why don't I see other SQL Instances on my LAN?

I have installed SQL Server more often that I'll like to remember. I've installed everything from enterprise to Express platforms, andSQL 2005 to SQL 2014 dev versions.

I've never had this problem until I installed SQL 2014 DEV on my development PC.

The problem I'm having is that when I try to connect to as SQL instance, they do not get listed when I try to browse for other instances on my local network. If I know the name of the host and instance, I can type it and it connects just fine. I just don't understand why I can't get them to list in the Browse for Servers (Network tab) dialog.

Any help would be appreciated.

Thanks.