At any given time, a user's privileges are determined by the user's Role relative to the Network she is current in. This is important to keep in mind in cases where a user has one Role in one Network and another Role in another Network. For example, if a user has Administrator status in the Finance Department Network and Member status in the College of Arts and Sciences (CAS) Network, she can promote other users in the Finance Department Network only when she is in the Finance Department Network, and she can discover new Communities in the CAS Network only when she is in the CAS Network. Therefore, if this user is currently in the Finance Department Network, but wants to discover Communities in the CAS Network, she will need to move from the Finance Department Network to the CAS Network.
To move between Networks, click on the name of your current Network, which appears just to the right of the Network Settings gear icon in the left hand corner of the upper banner. From here, you can move to Subnetworks of the Network you're currently in or move to any other Network in your organization for which you have a Role. You cannot explore Networks for which you do not have a Role. To gain access to a Network for which you do not currently have a Role, you will need to be invited by an Administrator in that Network.