This study was conducted to examine the effectiveness of treatments for acute whiplash injury. First, this study examined whether providing active management consultations was more effective than usual care (step 1) in the emergency department. Secondly, the study evaluated whether a physiotherapy package was more effective than one additional physiotherapy advice session in patients with persisting symptoms (step 2). For step 1, 3851 patients were randomized to either usual care of active management. For step two, 599 patients were allocated to either advice or a physiotherapy package. Assessment at 12 months revealed that the provision of active management consultation did not lead to additional benefit. Furthermore, a physiotherapy package gave a modest acceleration to early recovery of persisting symptoms but was not considered cost-effective.