5.1 The National Disability Insurance Scheme (NDIS) represents a significant new area of Commonwealth responsibility and expenditure with respect to people with disability in Australia. The focus of this chapter is on decision-making by participants in the NDIS. It outlines existing structures that facilitate decision-making by participants; illustrates how decision-making might operate if the Commonwealth decision-making model were implemented; discusses possible approaches to issues concerning interaction between NDIS supporters and representatives with state and territory appointed decision-makers; examines appropriate safeguards within the context of the NDIS; and proposes education, training and guidance in relation to decision-making and the NDIS.