Introduction: Persons with serious mental illness (SMI) are at high risk for cardiovascular disease (CVD), with CVD mortality with rates at least twice those of the overall US. Potentially modifiable CV risk behaviors (tobacco smoking, obesity, physical inactivity, unhealthy diet) and risk factors (hypertension, diabetes, dyslipidemia) are all markedly elevated in persons with SMI. This vulnerable population often has substantial challenges related to cognitive impairment and psychiatric symptoms in addition to high prevalence of substance use, low income and social isolation. Accomplishing meaningful reductions in CVD risk for persons with SMI will require special efforts to develop interventions to promote CV health in this high-risk group. Our objective was to determine the effectiveness of an 18-month comprehensive CVD risk reduction intervention in adults with SMI. Hypothesis: The active intervention is more effective than the control condition in reducing CVD risk as assessed by the global Framingham Risk Score (FRS). Methods: We conducted a NHLBI-sponsored RCT in 269 adults with SMI who had at least one of the following CV risk behaviors/ factors: BMI≥25 kg/m 2 , tobacco smoking, hypertension, diabetes, or dyslipidemia. Participants were recruited from four locations of an outpatient community mental health organization. Those in the active intervention received an 18-month individual-level intervention delivered by a health coach and a nurse providing 1) tailored CVD risk reduction counseling; 2) collaboration with physicians to implement appropriate management of CVD health risks; and 3) coordination with mental health staff and social supports to encourage and motivate attainment of individual CV health goals. We also provided training and resources to promote group physical activity classes, and a dietician to consult with kitchen staff to provide healthier meals (accessible to all mental health program attendees). Results: At baseline, mean(SD) age was 48.8(11.9) years, range 21-71. Of 269, 48% (N=128) were male, 46% (125) were African-American, 84%(226) received disability, 59%(159) had schizophrenia/schizoaffective disorder, 25%(67) had bipolar disorder, and 14%(38) had depression. BMI was 33.7(7.2) kg/m 2 ; 51% (138) smoked tobacco, 52% (141) had hypertension, 35% (93) had diabetes, 65%(175) had dyslipidemia. Mean(SD) baseline global FRS was 12.1(12.1)% overall, 16.9(14.6)% for men, 7.9(6.8)% for women. By October 15, 2018, 94%(253 of 269) participants completed the trial and had 18-month data collected. Eighteen-month data collection for the trial will conclude in November, 2018. Conclusion: Unless effective interventions that effect CV health outcomes are implemented, populations with SMI will continue to lag far behind the nation’s CVD goals. The IDEAL intervention is well positioned to address all CV risks in persons with SMI.