F.W. Riggs describes ‘Sala Model’ as

Public administration is a field in which administrators serve communities to advance the common good and effect positive change. Public administration professionals manage at all levels of government (local, state, and federal) as well as nonprofit organizations.

Public administration is often regarded as including also some responsibility for determining the policies and programs of governments. Specifically, it is the planning, organizing, directing, coordinating, and controlling of government operations.