“…Common factors, including elements of the therapeutic relationship, are often posited to be at least partially responsible for the frequently observed lack of between-condition differences in efficacy across therapeutic modalities ( Messer and Wampold, 2002 ). Our team’s prior clinical HIV/STI prevention intervention studies with youth have found fewer between-condition outcomes than expected, despite carefully and successfully ensuring distinction between modalities via use of separate therapists across conditions, separate supervision throughout the course of the study, and validated fidelity metrics that supported our capacity to deliver distinct content and clinical approaches in these interventions ( Feldstein Ewing et al, 2013 , 2014 , 2015 , 2016b , 2022 ; Mackiewicz-Seghete et al, 2022 ; Dash et al, 2023 ). As such, our observation of minimal differences between intervention conditions likely does not reflect intervention contamination and/or therapist overlap; rather, we posit that these outcomes reflect the presence and salience of common relational factors such as youth: provider relationship factors, and their impact across all modalities of HIV/STI prevention intervention programming ( Miller and Moyers, 2015 ).…”