Synopsis As Introduced Creates the Rebuild Illinois Mental Health Workforce Act. Provides that the purpose of the Act is to preserve and expand access to Medicaid community mental health care in Illinois to prevent unnecessary hospitalizations and avoid the criminalization of mental health conditions. Establishes add-on payments for the following community mental health services to be paid beginning with State Fiscal Year 2023 and continuing for each State fiscal year thereafter: individual therapy services; community support-individual services; case management services; and assertive community treatment services. Requires monthly directed payments to community mental health providers of community support team services or assertive community treatment services. Provides that such directed payments shall be based on the number of Medicaid users, as defined, who receive services from the provider in the base year. Provides that the add-on payments established under the Act shall apply to Medicaid services provided by a contracted managed care organization or entity and services paid for directly by the Department of Healthcare and Family Services. Provides that no base Medicaid rate or Medicaid rate add-on payment or any other payment for the provision of Medicaid community mental health services in place on July 1, 2021 shall be diminished or changed to make the reimbursement changes required under the Act. Requires the Department to apply for federal approval to implement the Act. Provides that implementation of the add-on payments is conditioned on the receipt of federal financial participation for such payments. Effective immediately.