The efficacy of legislation in reducing firework associated injuries is uncertain as is the nature of the problem within the United Kingdom (UK). In September 1996 the legislation governing firework sale in Northern Ireland was relaxed thus equalling that of the rest of the UK. For the 2 years following the change in legislation we prospectively assessed those patients who were admitted with a firework injury over the Halloween period. We then compared these results with retrospective data for the 3 years prior to the change in firework law. In the pre-legislation series the mean number of patients admitted annually was 0.38 per 100,000 while in the post-legislation series the mean was 0.43 per 100,000. Blast injury to the hand was the commonest injury accounting for 53% of cases in both series. Burn injuries were the second commonest form of injury comprising 30% of all admissions. Of those admitted with a hand injury 47% had at least one finger terminalised and nearly half of those patients admitted with burns (44%) required skin grafting. We conclude that early evidence suggests that liberalisation of the law on firework sale has not resulted in a significant increase in firework related injuries requiring hospital admission.