A teacher in a mainstream classroom identified six children with behaviour difficulties or learning difficulties who were not receiving any assistance outside of the classroom. The teacher was to independently complete a functional assessment of each child to reach a hypothesis about the cause of the difficulty, and then choose and implement an appropriate intervention. Treatment integrity was monitored throughout the interventions to ensure correct implementation. It became apparent that the teacher was unable to complete adequate functional assessments or maintain appropriate interventions because of the time constraints associated with being in a classroom and her lack of specialist knowledge.