Project Summary People with serious mental illness (PSMI, e.g., schizophrenia, bipolar disorder) die on average 20 years earlier than the general population mostly due to preventable chronic diseases (e.g. cardiovascular disease, diabetes, obesity). Latinxs simultaneously account for higher rates of serious mental illness (SMI) and chronic diseases compared to non-Latinx whites. Puerto Ricans are United States (US)-born citizens with one of the highest rates of SMI and chronic disease risk and mortality among Latinxs in the US. These disparities have been further aggravated after the healthcare system collapse in the aftermath of Hurricane María, the 2020 earthquakes in the Southwest region of Puerto Rico (PR) and the COVID-19 pandemic. Early interventions on physical health parameters are urgently needed to reduce morbidity and premature mortality among PSMI. Primary care physicians play a key role in these efforts.24 However, as the team has demonstrated in their previous research in Puerto Rico, provider stigma towards SMI hinders prevention efforts. Healthcare manager interventions (HMI) can be helpful to address these identified barriers and support the use of existing services more efficiently by improving care coordination, patient activation and chronic disease prevention. Despite its effectiveness, few HMI interventions are available for Latinxs with SMI. As part of PHSU’s RCMI U54 renewal application (RFA- MD-22-002), the proposed Behavioral Project aims to test Bridges to Better Health and Wellness (BRIDGES), developed by Dr. Cabassa (Co-I) 37 and adapted by Dr. Rivera-Segarra (PI) at PHSU with RCMI support. BRIDGES is the only culturally adapted Multilevel HMI for Latinxs with SMI. However, although culturally adapted, the effectiveness of BRIDGES compared to treatment as usual group (TAU) in PR has not yet been examined. The proposed study aims to address this important public health gap by deploying a Hybrid Type 1 effectiveness-implementation randomized controlled trial, useful for promising interventions for which effectiveness and implementation have not been tested throughout (such as BRIDGES). In light of thus, the aims of this study are: 1) Test the effectiveness of BRIDGES vs Treatment as Usual (TAU) and 2) Examine the implementation and public health impact of BRIDGES.