All participants will receive a 12-session version of Emotion Regulation Therapy delivered weekly via synchronous telehealth using videoconferencing software and an asynchronous Internet-based online platform to supplement the content covered in each session.

The initial stage of treatment focuses on psychoeducation about anxiety/depression, the impact that these cognitions/behaviors/emotions have on recent situations, and self-monitoring of worry/anxiety/depression. The sessions focus on the development of skills that help understand and regulate one's emotional experience (i.e., recognizing emotions when they are happening, identifying the meaning of a given emotion experience, soothing oneself in the context of negative emotional experiences). Following the development of these skills, sessions focus on the application of somatic awareness and emotion regulation skills while imagining emotionally evocative themes. The remaining session focuses on terminating therapy, relapse prevention, and future goals. An Internet-based online platform will be used to promote engagement with and increase accessibility to between-session skills practice and treatment-related activities (e.g., self-monitoring, session summaries, worksheets).

The Attentional Control Scale (ACS) is a 21-item measure used to measure difficulties with concentration associated with problems regulating emotions. The focusing and shifting subscales of the ACS align with the two attention emotion regulation (ER) skills taught in ERT.

The decentering subscale of the Experiences Questionnaire (EQ-D) is an 11-item subscale assessing one's ability to distance themselves from their emotional experience, which is one metacognitive ER skill taught during ERT. Higher scores on this subscale indicate better ability to distancing oneself from one's emotional experience.

The reappraisal subscale of the Emotion Regulation Questionnaire (ERQ) is a 6-item measure of the ability to regulate emotions, using the strategy of reappraisal. Higher scores on this subscale indicate a better ability to regulate emotions using the strategy of reappraisal.

The Valuing Questionnaire (VQ) is a 10-item measure of the degree to which patients live by their values in daily life. It uses a 7-point Likert scale (0-6) to assess progress and obstructions to valued living. Higher scores on this measure indicate more valued living.

The Patient-Reported Outcomes Measurement Information System (PROMIS) Item Bank v. 1.0 - Emotional Distress - Depression - Short Form 8a will be administered to assess for depression severity. Higher scores on this measure indicate greater depression severity.

The Sheehan Disability Scale (SDS) is a 4-item scale which assesses impairment in work, social life/leisure activity, family life/home responsibilities, and overall functioning. Higher scores on this measure indicate greater impairment.