The mental and behavioral health care needs of Americans, including veterans, have substantially grown over the past few decades. As the nations largest provider of mental health care, the U.S. Department of Veterans Affairs (VA) faces some of the greatest challenges in meeting the mental health care needs of its population. These challenges are exacerbated by a shrinking mental health care workforce and provider shortages in low-income and rural communities. To address these challenges, and at the request of VA, the National Academies of Sciences, Engineering, and Medicine Forum on Mental Health and Substance Use Disorders held a public workshop on Improving Access to High-Quality Mental Health Care for Veterans to explore the U.S. landscape for mental health care services, including telehealth services. The workshop considered ways to improve veterans timely access to high-quality care for mental health conditions. In particular, it explored internal and external best practices for three critical needs for mental health access (known as tripartite access in VA): urgent/crisis, engagement, and sustained access. This proceedings document summarizes discussions at the workshop.