Abstract Background It is well-established that core clinician interpersonal behaviours are important when treating depression, but few studies have evaluated whether outcome is determined by clinicians׳ general behaviour rather than by the perception of the individual being treated. Methods In the NIMH TDCRP, 157 patients rated their clinician׳s genuineness, positive regard, empathy and unconditional regard during cognitive behavioural therapy, interpersonal therapy or clinical management with placebo. The association between averaged ratings for each of 27 clinicians and their patients׳ self- and observer-rated depression outcomes was evaluated, adjusting for the deviation of individual patient ratings from the average for their clinician and other potential confounders. Results Clinicians in the clinical management condition were rated on average as less genuine and less empathic than those in the psychotherapy conditions. Clinicians׳ average genuineness, positive regard and empathy were significantly associated with lower depression severity during treatment, but not with recovery from depression, after adjusting for the deviation of the individual patient׳s rating of their clinician from the average for that clinician, treatment condition and baseline depression severity. Clinician unconditional regard was not significantly associated with outcome. Limitations Using averaged ratings of clinician behaviour likely reduced statistical power. Conclusions Clinicians׳ ability to demonstrate genuineness, positive regard and empathy may represent a stable personal characteristic that influences the treatment of depression beyond the individual clinician–patient relationship or an individual patient׳s perception of their clinician. However, clinicians׳ ability to demonstrate these behaviours may be poorer when delivering an intervention without a specific rationale or treatment techniques.