In Australia, Canada and the US social exclusion is associated primarily with the private rental sector rather than with social housing as in some European countries. By European standards, these three countries have large private rental sectors. Increasingly it is the working poor in insecure and low wage jobs and households dependent on social assistance (welfare) who are concentrated in the private rental sector. The paper examines the nature of social exclusion associated with a largely unregulated, private rental sector in these three countries. The location of private rental housing contributes to exclusion from facilities and opportunities. Minimal legal protection results in insecurity and lack of control over housing. Exposure to market forces at the lower end of the rental market can contribute to financial stress and acceptance of inadequate or unsuitable accommodation. The uncertainty and mobility associated with private rental restricts participation in local communities and wider citizenship. The second part of the paper looks at government policy responses to social exclusion in the private rental sector in these three market liberal countries. Governments have adopted pro-market policies that fail to recognise social exclusion experienced in the private rental sector and have instead focused primarily on issues of housing affordability. In Australia, Canada and the US housing policy has fragmented to the extent that there is arguably no national housing policy in these three countries. There has been a retreat from broader housing policies, including supply subsidies for social housing. Instead there is heavy dependence on de facto housing allowances that are part of social assistance (welfare) programs and other housing allowances, which are intended to make some contribution to housing costs, often without an affordability benchmark. Increasingly there are conditions attached to these allowances which are designed to get households off social assistance (welfare) and into work. Getting a job is seen as the route to social inclusion in these three market liberal countries. Whilst there are many similarities between Australia, Canada and the US in approaches to social exclusion in the private rental sector, there are some significant differences as well. The paper concludes by exploring some of the factors that have shaped these differences including the nature of federal government systems, institutional factors and cultural and political differences. These factors have impacted both on perceptions of social exclusion in the private rental sector and the policy response of various levels of government.