Problem behaviors, such as aggression, self-injury, and disruption, are common reasons for referrals for individuals with developmental and intellectual disabilities (Emerson et al. 2001;Murphy et al. 2009). Several studies using parental report indicate that children with problem behavior are also more likely to have sleep difficulties (e.g., Mazurek et al. 2013;Rzepecka et al. 2011), while others suggest that the two domains are not correlated (Dominick et al. 2007). There has also been support from a direct observation study suggesting that individuals who exhibit problem behavior have more sleep difficulties when compared to national norms (Piazza et al. 1996), but these findings are correlational in nature and do not provide information about a temporal relationship. Thus, it is unclear from current research whether sleep difficulties and problem behavior vary together (e.g., whether behavior is worse on days following low sleep) or whether they are temporally unrelated (Brylewski and Wiggs 1999).In evaluating the relationship between problem behavior and sleep, it is helpful to consider the three-term operant model of antecedents, behaviors, and consequences. Motivating operations are defined as an antecedent event that alters the value of a consequence. One type of motivating operation, an establishing operation, temporarily increases the value of a reinforcer and evokes behaviors that have historically resulted in that reinforcer (Laraway et al. 2003;Michael 1982). Sleep has been identified as a potential motivating operation for problem behavior, especially behaviors maintained by negative reinforcement (e.g., Langhorne et al. 2013). In other words, sleep deprivation (or fatigue) may increase the reinforcing value of escape from demands and make problem behavior maintained by escape more likely to occur when the child has limited sleep. In a practical example, a child may find math work more aversive if he/she is tired, resulting in an increased reinforcement value of escape from math. If the child has historically escaped math work by engaging in aggression, he/she is more likely to engage in this aggression when he/she is tired.There have been a few studies that use direct observation to demonstrate a temporal relationship between sleep and problem behavior and provide support for the idea that lack of sleep might serve as a motiving operation for problem behavior. Studies using pharmacological treatments to improve sleep have found that daytime problem behavior decreases with sleep improvement (Eshbaugh et al. 2004;Sovner et al. 1999). Other support for a temporal relationship between sleep and problem behavior arises from studies evaluating the effects that sleep might have on functional analyses (FAs) outcomes. FAs are usually conducted in a therapeutic setting to determine environmental variables that might maintain an individual's problem behavior. A therapist manipulates the environmental antecedents (e.g., presents demands, appears busy or unavailable for attention, removes a preferred item) an...