The essentials of single-session interventions

Many individuals who seek mental health care will attend only a single session, whether by choice or due to systemic barriers. At the same time, clinicians are navigating increasing demand, long waitlists, and limited capacity to provide ongoing care. This creates a disparity between the need for services and the structure of traditional, multisession therapy models.

In response to these challenges, single-session interventions (SSIs) have emerged as a scalable, evidence-based approach, designed to maximize the impact of a single clinical encounter, with the goal of expanding access to mental health care. Rather than viewing a single session as incomplete care, SSIs are designed to offer therapeutic change in a standalone session. Still, challenges remain, including the need for more research on effectiveness across diverse populations, clearer payment pathways, and broader adoption.

[Related: Improving population health through single-session interventions]

SSIs are structured programs that intentionally involve only one visit (usually the standard 50 minutes) or encounter with a clinician.¹ The defining feature of SSIs is intentionality. They are designed to offer meaningful benefit in one session.

The SSI approach is known by a variety of names. Through research on the topic, the term “single-session intervention” has been used interchangeably with “single-session therapy,” “one-session treatment,” “ultrabrief interventions,” or “one-at-a-time therapy.”

Even though SSIs can be tailored for many purposes and vary in approach, most share several common elements:

• Intentional structure. SSIs are deliberately designed to occur in one planned session or interaction, rather than being a truncated version of longer therapy.²
• Theory-driven, evidence-based content. Most of the session tends to focus on evidence-based principles, such as cognitive restructuring, behavioral activation, and motivation.³
• Targeting proximal mechanisms of change. SSIs focus on shifting immediate beliefs, agency, and coping strategies to drive long term outcomes.³
• Active engagement and self-reflection. SSIs use exercises to reinforce learning and internalization, as well as emphasize concrete steps to apply skills beyond the session.³
• Flexibility in delivery. SSIs can be delivered in-person, digitally, self-guided, or clinician-led. SSIs have been used in a variety of settings, including clinics, schools, primary care, and via digital platforms.³
• Focus on immediate, meaningful impact. Any single session can yield benefits such as symptom reductions and increased support-seeking.⁴
• Therapeutic alliance. Even though the time together is limited, the connection between the patient and clinician is still an important determinant for success.³
• Standalone or adjunctive use. SSIs can function independently or complement longer-term treatments within broader care systems.²

Findings across all populations

• Meta-analyses show small-to-moderate positive effects of SSIs on mental health outcomes across randomized trials.⁴
• Effects are smaller than multi-session therapies, but SSIs offer significantly greater scalability and reach.²

To dive deeper into what the research says, see the References section.

Youth populations

• Strong evidence of SSIs for tackling anxiety symptoms in youth populations (including specific phobias and generalized anxiety).⁶
• Meta-analysis of 50 randomized control trials when comparing SSIs for mental health problems against placebo or care as control. SSIs for youth psychological problems demonstrated a significant beneficial effect.⁶
• Research on significant, but limited, positive effectiveness for youth symptoms: anxiety, depression, conduct disorder, substance use.^4,6
• When comparing SSIs with active controls such as brief psychoeducation or psychosocial placebo, the research is less promising.⁶

Adult populations

• SSIs demonstrated symptom reduction in large scale and digital trials across multiple mental health conditions (e.g. alcohol use and pain management).³
• Improvement in self-efficacy characteristics.³
• Research on significant positive effectiveness for adult symptoms: anxiety, depression, eating problems, suicide related thoughts/behaviors, substance use.⁴
• There is still a need for more research on long term effectiveness of these SSIs with combatting mental health concerns.

Reimbursement challenges: More research and payment options are needed

• Dedicated billing codes for SSIs are not yet established.
• Limited research currently exists on reimbursement models for SSIs.⁷
• Development of reimbursement pathways will be critical to support sustainable implementation of SSIs in routine clinical practice.

How SSIs can help address the mental health treatment gap

• High unmet need. There is a global mental health treatment gap, where there is a stark difference between the number of people diagnosed with a mental health disorder and those who are diagnosed vs. those who receive care. In the United States, there are about 1 in 4 adults and 1 in 5 adolescents living with a mental disorder. But only half receive mental health treatment.⁵
• Structural barriers to access and system-level mismatch. Cost, provider shortages, long waitlists, geographic limitations, overcoming social stigma, and time constraints limit engagement. Traditional therapy models can create bottlenecks such as cost, provider shortages, long waitlists, geographic limitations, and time burden.²
• Low treatment completion. Many patients start therapy, but don’t stick with it. In fact, research indicates that the most common number of sessions attended is one.⁴

• Single-session consultation for emotional and behavioral healthopens in new window
  Materials to assist clinicians in implementing SSIs
• Lab for scalable mental health: Project youth empowerment and support (YES)opens in new window
  Self guided mental health tools for teenagers
• Lab for scalable mental health: Research posters, research talks, professional developmentopens in new window
  Materials for researchers and clinicians who want to learn more about SSIs