Schoolwide positive behaviour support (SWPBS) programs have proven to be largely effective at reducing problem behaviour in schools. Full implementation of SWPBS has been associated with positive behavioural and academic outcomes. However, despite their effectiveness, implementation rates of SWPBS remain low. For SWPBS to be sustained, a number of barriers need to be addressed. Insufficient investment from school administrators, staff buy-in, and school culture are the main barriers to successful implementation. By attending to these barriers, the chances of successful implementation of SWPBS are enhanced.