We examined the role of specific therapist verbal behaviors in predicting successful completion of Parent?Child Interaction Therapy (PCIT) in 22 families, including 11 families that successfully completed treatment and 11 that discontinued treatment prematurely. The children were 3 to 6 years old and diagnosed with oppositional defiant disorder (ODD). Chamberlain et al.'s (1986) Therapy Process Code (TPC) was used to measure therapist verbalizations during therapist?parent interactions during the initial clinical interview and the second treatment session. Results indicated that therapists' use of the categories Question, Facilitate, and Support during these sessions accurately predicted treatment dropout versus completion for 73% of families. Findings suggest that the early therapist?parent relationship in PCIT may be critical to successful treatment completion.