ACMA's main roles in the introduction of digital radio include frequency planning, transmitter licensing, and declaring the start-up day. Frequency planning involves preparing digital radio channel plans and a frequency allotment plan. Transmitter licensing involves issuing new multiplex transmitter licenses and allocating license categories. ACMA has determined timeframes for key tasks in 2007 and 2008, including developing channel plans, varying plans if needed, inviting license applications, and issuing licenses, with the goal of declaring a start-up day in December 2008.