Therapeutic (homework) tasks are a characteristic strategy in behavioral psychology to achieve clinical change. The aim of the present study is to determine how behavioural therapists assign therapeutic tasks and review their compliance. Observational methodology was used to analyse the verbal interaction of therapists and clients in 211 recorded sessions (19 complete successful cases) using a validated coding system (SIST-INTER-INSTR). The values for inter- and intra-judge reliability were from good to excellent. The study shows that behavioural psychologists offer motivating verbalisations when assigning therapeutic tasks. During the review of task compliance, therapists frequently provide positive reinforcement when clients report complete compliance with the assigned task but stop the review of tasks when clients report non-compliance or only partial compliance with the task. These sequences provide information about how behavioural therapists provide instructions for therapeutic tasks and review their compliance. This is a first step to study how these verbal sequences favour the establishment of TC and the effectiveness of treatment.