Problem behaviours occur in approximately 10 to 15% of individuals with intellectual disabilities and these behaviours most often include aggression and self-injury. Families who support young adults with multiple disabilities and problem behaviour at home often experience costs to their psychological, physical, financial and emotional wellbeing. Respite care evolved to allow families short breaks from care giving and to support families in looking after their family members at home. Furthermore, problem behaviour severely limits opportunities for individuals with multiple disabilities to interact adaptively with their environments and develop positive behaviour skills that increase the possibility of living independently in their adult years. The present study aimed first to demonstrate the utility of functional analysis of problem behaviour in respite care, and then, to reduce food stealing and pica exhibited by a young adult with multiple disabilities attending a respite care centre. Following a functional analysis that indicated food stealing and pica had the probable function of hunger reduction, two positive behaviour support plans were developed. These interventions, conducted at the respite centre three days a week by centre staff, involved strategies to teach the participant to sign “eat” in New Zealand Sign Language (NZSL) to gain access to food and increase accessibility of food in the environment to reduce pica. The results showed that introducing the NZSL sign reduced food stealing to near zero within three weeks and pica was eliminated following the combined approach of functional communication training and antecedent manipulation. Use of the communicative sign was maintained at follow-up and food stealing remained at near zero, while pica remained at zero one-month following the intervention.