Allegheny County Department of Human Services (ACDHS) seeks to enhance and expand its successful pilot of the Mental Health/Child Welfare Community of Practice System of Care (CoP SOC) to improve access, coordination and quality of mental health (MH) services for youth and families involved in the child welfare (CW) system. The population of focus will be families and their children/youth experiencing a Serious Emotional Disturbance (SED) or early onset Serious Mental Illness (SMI), ages 5 to 21, who are also involved with CW or with both CW and Juvenile Justice (JJ). ACDHS data demonstrates that families active with CW are frequently involved with multiple systems, including MH and JJ, and have complex needs. In fiscal year (FY) 18/19, 59,142 individuals received MH services in Allegheny County (AC); of those, 2,142 children were dually active with the MH and CW systems. Also in FY 18/19, there were 3,539 families active with CW. For 73% (2,571) of these families, at least one family member received MH services during that year, and 40% of families had more than one family member who received MH services. Youth who are concurrently active with CW and JJ, commonly referred to as “crossover youth,” also have high MH service utilization. Of the 501 crossover youth in 2018, nearly all (93%) received MH services at some point in their lives. Children and youth involved with systems such as CW, MH, and JJ not only face disproportionately high rates of emotional or behavioral disorders and developmental delays, but also often experience out-of-home placement and lower rates of being placed in a family setting or achieving placement stability. The primary goal of the CoP SOC is to improve the access, coordination and quality of MH services for youth and families experiencing SED or early onset SMI who are also involved in CW or CW/JJ. The CoP SOC proposes to serve at least 250 participants over the entire project: 30 in year 1, 50 in year 2, and 60 in years 3 and 4 through the MH referral pathway; and 10 in year 1 and 20 in years 3 and 4 through a new model of MH Family Case Management (MHFCM). Objectives include: competitively procuring an MH CoP provider to implement the MHFCM model; full implementation of the previously piloted MH referral pathway across CYF regional offices for multi-system involved youth and families; cross-system best practice training; attaining Medicaid reimbursement for the MH Family Case Management model; and identification, testing, and implementation of best practices for serving multi-system youth who are transition age.