This study seeks to further test the effectiveness of Primary Care Brief Mindfulness Training (PCBMT) across multiple geographically distinct VHA primary care settings that serve diverse Veteran populations and begin to understand important implementation factors with a hybrid type I randomized controlled trial in 300 primary care patients with psychological distress. The study aims include comparing PCBMT to a transdiagnostic problem solving group (Moving Forward, MF) on clinical outcomes, testing mediators and moderators of treatment gain in PCBMT and MF, and assessing implementation barriers and facilitators to inform future implementation efforts. The investigators hypothesize that Veterans randomized to PCBMT will experience larger decreases in psychological distress than participants randomized to MF and changes in transdiagnostic processes will mediate the relationship between changes in mindfulness and psychological distress.