In creating a career ladder for all staff we recognized that we needed to have a track [1] for those with an MLIS, and those without one. At this same time we made the decision to not require the MLIS for the branch manager job. Therefore we created two tracks that require a college degree - the access/library manager track [1] (MLIS preferred, but not required) and the engagement/librarian track [1] (MLIS required). Because not all positions in the librarian/engagement track are managers, we decided to call any engagement staff who supervise people "supervisors" to help differentiate between the two tracks.
Links:
[1] http://my.metrolibrary.info/drupal/sites/default/files/documents/career%20tracks.pdf