Objective: Significant change events are helpful moments within a psychotherapy session that have been shown in previous research to relate strongly to outcome. They are special moments and therefore provide rich data for research into understanding therapeutic process. This study investigated clinical and linguistic features of these helpful moments using and comparing both human ratings and computerized text analysis strategies. Method: Significant change events versus non-event passages were studied within 1195 word blocks of transcribed psychotherapy for 20 participants with diagnoses of comorbid depression and personality disorder. Significant events were determined manually by independent raters using the Helpful Aspects of Therapy (HAT) form linked to the Helpful Aspects of Experiential Therapy Content Analysis System (HAETCAS). Mergenthaler's Therapeutic Cycles Model (TCM)-computerized text analysis, identified significant events via linguistic markers. The Linguistic Inquiry and Word Count (LIWC) differentiated emotional and cognitive components. Results: Significant events included statements reflecting emotional and cognitive awareness and insight, and moments of alliance strengthening. These events were saturated with both positive and negative emotion words, particularly anger and sadness, and more cognitive insight words. Conclusions: Significant moments of psychotherapeutic movement featured high therapeutic alliance. There was evidence of the integration or working through of positive and negative emotional content with cognitive insight - meaning both emotion and cognition were important in these interchanges. Practitioner points: This study found that significant events in therapy were characterized by high levels of both emotional and cognitive language, and alliance strengthening. Linguistic analysis methods provide important data on psychotherapeutic processes which can be useful in guiding clinicians and improving treatment outcomes.