<p>Deliberate firesetting is an international problem with significant personal and economic cost. Interest in fire has previously been identified as a unique predictor of deliberate firesetting, however little is known about how fire interest interacts with other factors to produce firesetting. This research aimed to gain a deeper understanding of the role of fire interest by exploring how this construct interacts with previous exposure to fire and aspects of self and emotional regulation, and how this relates to firesetting behaviour. Two anonymous online studies were conducted among New Zealand adult community samples: Study 1 examined the relationship between fire interest, previous exposure to fire, emotional dysregulation, impulsivity, and sensation seeking (N = 146); Study 2 replicated the first study and explored the relationship between these factors and engagement in deliberate firesetting (N = 149). Results from both studies showed that only previous exposure to fire and sensation seeking were consistently positively correlated with fire interest, however, when other variables were controlled for via multiple regression analysis, the thrill/adventure seeking facet of sensation seeking was the only significant predictor of fire interest. In Study 2, logistic regression showed that only fire interest and impulsivity were significant predictors of deliberate firesetting. Moderation analyses indicated that thrill/adventure seeking moderates the relationship between fire interest and firesetting behaviour, while impulsivity does not. These findings extend previous research and theory by providing an initial understanding of how various factors may influence an individual’s level of fire interest and their engagement in deliberate firesetting. </p>