Pilot Effectiveness Trial of an ACT Self-help Workbook Tailored Specifically for Prisons

Inclusion Criteria: * 18 years of age or older * Reading level of 6th grade or higher determined by the Wide Range Achievement Test * Moderate or severe anxiety and/or depression determined by the Beck Depression Inventory-II (BDI-II) and Beck Anxiety Inventory (BAI) * No active self-harm or active suicidal intent * No scheduled transfer or release for at least three months * Must be willing and able to participate, including having permission and ability to use study materials, such as paper and a writing utensil Exclusion Criteria: * Unable to provide informed consent * Active self-harm or suicidal intent * Scheduled transfer or release within three months