The fact so many businesses buy cover through the TRIA program suggests they believe it meets their needs, but this may not be true in practice. In our experience, the most common cause of loss in this market is non-damage business interruption, which arises from incidents near to the insured’s premises, a supplier’s property, or at site operated by their utility provider. The problem here is that TRIA cover attaches to, and mirrors underlying property or commercial combined policies. These policies may not cover the impact of a terrorist attack on the insured’s revenues if that attack does not take place at their premises.