The present study investigated links between the observer-rated process of psychotherapy and 2 key psychotherapy relationship constructs (i.e., working alliance and attachment to the therapist) in the context of a brief, attachment-based, home-visiting, mother–infant intervention that aimed to promote later secure infant attachment. Additionally, links between observer ratings of intervener and mother contributions to process were examined. Participants included 85 economically stressed mothers of first-born, 5.5-month-old, temperamentally irritable infants. Therapists included 2 doctoral-level and 4 master’s-level home visitors. Observer-rated therapist psychotherapy process variables (i.e., warmth, exploration, and negative attitude) were not linked to maternal ratings of working alliance. Therapist warmth, however, was positively associated with maternal ratings of security of attachment to the therapist, and therapist negative attitude was positively related to maternal ratings of preoccupied-merger attachment to the therapist. As expected, both therapist warmth and exploration were positively associated with both maternal participation and exploration. Therapist negative attitude was inversely related to maternal exploration, but not to maternal participation. Results support the idea that attention to the psychotherapy process and relationship may be important in the context of a brief home-visiting parenting intervention with a nonclinical sample. (APA PsycInfo Database Record (c) 2016 APA, all rights reserved)