BAR HARBOR — The school committees in all the Mount Desert Island Regional School System towns are voting this month to take part in planning to replace the current school system structure with a regional school unit (RSU), which advocates say would be more equitable and efficient.

Superintendent Mike Zboray says it is an early step in a long process and doesn’t commit any school committee or town to supporting the creation of an RSU. In the RSU model, there is a single school board and a single annual budget that covers all the schools in the district.