Date of Award


Document Type

Scholarly Project

Degree Name

Master of Occupational Therapy (MOT)


Occupational Therapy

First Advisor

Sonia Zimmerman


Mental Disorders -- therapy; Occupational Therapy -- methods; Substance-Related Disorders -- therapy


The purpose of this project was to develop a resource manual for occupational therapists to guide treatment planning for persons with a co-occurring mental illness and substance use disorder, according to the stages and components of the Integrated Dual Disorder Treatment (IDDT) Model.

A comprehensive literature review of the issues facing persons with co-occurring disorders, the IDDT model, and the role of occupational therapy for persons with co-occurring disorders was conducted. The literature supported the effectiveness of the IDDT model, and indicated justification for occupational therapy’s implementation of the IDDT model.

A resource manual was developed to support occupational therapists’ the development of effective treatment planning for persons with co-occurring disorders through the implementation of the IDDT Model. The Person-Environment-Occupation Model was selected as the guiding occupational therapy model to utilize in conjunction with the IDDT Model.

The IDDT Model is widely recognized as an evidence-based approach to service delivery to persons with co-occurring mental illness and substance use disorder. Occupational therapists, as members of the interdisciplinary IDDT team, have the unique ability to improve persons’ participation in meaningful occupations, as well as developing a sense of wellness and improved quality of life.