Every DISP member must designate both roles, and each has prerequisites a staff member must meet before taking it on.
The Chief Security Officer (CSO) must be a senior executive, typically a director, board member, involved shareholder or other high-level executive. The CSO owns the company's DISP compliance and builds its security culture.
The Security Officer (SO) is the hands-on role: advising staff and management on security, annual reporting, annual security awareness training, managing clearances and reporting to Defence. An office manager, operations manager, IT manager or Defence project lead often fills it. The SO reports to the CSO.