Background: The physical health burdens and health-related behaviours (e.g., smoking, poor nutrition, sedentariness) associated with substance use disorders necessitate an integrated treatment response. Yet service fragmentation can preclude physical health from being addressed within specialist alcohol and other drug (AOD) treatment services that typically operate outside of primary care settings. Relative to the general population, people living with substance use problems are at an increased risk for developing many types of chronic illness, including cardiovascular disease, respiratory disorders, hepatitis C, and diabetes. Moreover, individuals who attend AOD treatment are 2.3-2.7- times more likely to have multiple (i.e., two or more) physical diseases when compared to those who never attend AOD treatment. Despite this, there has been little research attention given to understanding how the physical health disparities of substance using populations can be managed during specialist AOD treatment. Social ecological models recognise the multiple environmental influences that interact to affect the provision of treatment and treatment outcomes. Recovery capital approaches suggest that treatment of substance use disorders needs to promote resources among individual service users, augmenting the short-term effects of clinical intervention. Using social ecological models and recovery capital as a conceptual base, this thesis comprises four studies which aim to explore the integration of physical health care within specialist AOD treatment. The aim of Study 1 was to examine what empirically based guidance was available to the AOD workforce when addressing the physical health of those attending treatment. Study 2 aimed to better understand the nature and prevalence of physical health morbidities of people attending treatment for substance use disorders and how these are identified. Study 3 sought to examine the facilitators and barriers to the integration of physical health care within specialist AOD treatment settings. The aim of Study 4 was to explore the perceived role of physical health in the process of recovery from the perspective of the AOD workforce and people attending treatment for substance use disorders. Method: Study 1 consisted of a systematic review of 33 clinical practice guidelines for the treatment of substance use disorders. A grey literature search was used to identify guidelines from Australia and other international jurisdictions. Eligible guidelines were subject to data extraction that included i) guideline characteristics, ii) the physical health problems identified by the guidelines and iii) the recommendations made by the guideline for managing physical health and health-related behaviours. Appraisal of guideline quality and rigour was conducted