Over the last two decades, Australia, like many countries, has experienced widening inequalities in the social determinants of health. From 1996-2007, the former conservative government's policies increased inequality across Australian communities, despite achieving sustained economic growth [1]. Policy analysts argue that this was caused by government action on two levels. Firstly, by pursuing policies, such as disinvestments in public education and healthcare, that actively penalized those at the lower end of the social gradient [2]. Secondly, by contracting out government services to not-for-profit organisations, the government constrained the efforts of non-state actors to address the needs of disadvantaged individuals and communities [3].

In 2007, the Australian Labor Party ran for government on a platform of increased equality and social inclusion. Since taking office they have launched the Social Inclusion Agenda (SIA): an ambitious large-scale social policy initiative designed to re-orientate the delivery of social and public services and redress growing inequality. The government anticipates that the SIA will combat complex and intractable problems of exclusion and disadvantage by promoting social, economic and civic participation and by re-orientating the provision of welfare and social services [4]. Under the government's vision of a socially inclusive Australia, all citizens will have resources and opportunities to: participate in education and training; work in employed, voluntary, family or caring capacities; become engaged in their local communities; and have a voice to effect decisions which influence their lives [4]. While many hope that the SIA will achieve institutional change within government, significant emphasis is being placed on supporting and better facilitating non-state actors to address disadvantage. Primarily, these actors are not-for-profit organisations operating in the welfare sector. This approach is in keeping with international trends; welfare reform is increasingly concerned with altering the way in which welfare systems operate and are organized [5]; to achieve this re-organisation, governments are increasingly looking to the not-for-profit sector [6].

The SIA has the potential to significantly reduce inequalities in the social determinants of health, thereby bringing widespread benefits to individuals and communities. However, given the reliance on non-state actors, the SIA is a challenging and risky policy intervention. The choice of social inclusion as a policy framework adds another layer of complexity to this challenging implementation environment. Individuals who are disadvantaged or marginalised experience multiple, complex, and changing barriers to wellbeing and inclusion [1]. It is important to note that for services to be successful in promoting the inclusion of these individuals, they must be flexible, adaptive and locally responsive [1]. The SIA therefore faces an added challenge of allowing for local flexibility, while enforcing a new guiding principle for welfare and the delivery of services.

To ensure the success of the SIA, significant macro-level implementation is required between different levels, and across different departments, of federal and state governments. The government has also made a strategic commitment to the not-for-profit sector in order to deliver on the outcomes of the SIA. This means that the SIA must also be successfully adapted and implemented at the local level by these organisations. To facilitate this, the government aims to create new partnerships and opportunities to encourage not-for-profit organisations to deliver more innovative, integrated and holistic services for marginalised and disadvantaged people.

The not-for-profit (or third) sector has an important, and increasingly prominent, role in addressing the social determinants of health. Since the 1970s the sector has been an important facilitator of social and civic participation, and is understood to build social capital and promote social cohesion [7]. Research into the social determinants of health has now compiled a considerable body of evidence that links social participation, cohesion and some forms of social capital to health [8, 9]. The third sector is also fundamental to more explicitly public health-orientated activities: not-for-profit operations encompass health promotion, community development, community empowerment, and consumer participation [10]. Over the last two decades, the sector has become increasingly involved in the provision of social and public services, which support the health and welfare of the population [3, 7, 6, 11, 12]. Not-for-profits are also increasingly seen as important contributors to policies that impact the social determinants of health.

However, as Michael Marmot [13]: p160. argues, "[w]hile the real and potential contribution of the third sector to reducing health inequalities is recognised, there remains concerns about how the sector is supported, both to deliver its services and to effectively engage [with government] as a strategic partner".

The decision to implement the SIA primarily through the not-for-profit sector means that ultimately the success or failure of the policy resides within the organisational contexts of individual not-for-profits. Under the SIA, not-for-profit organisations face a new set of rules - how organisations respond to these rules will influence whether the SIA is realised at the local level [14]. Thus, successful implementation relies upon: the government putting in place the right infrastructure (e.g. funding structures) to allow organisations to address exclusion; the appropriateness of social inclusion as a framework for the sector; and the willingness and capacity of individual not-for-profits to engage with the agenda.

For Australia, the SIA is arguably one of the most significant broad-scale public health policies of recent times. With a focus on redressing inequality, increasing participation and social connectedness and providing better services and support to citizens, it has the potential to make significant inroads into inequalities in the social determinants of health. However, the reliance on the not-for-profit sector raises a number of questions: will there be sufficient change at a state and institutional level to allow not-for-profit organisations to successfully address exclusion? Will organisations respond to the challenges thrown down by the SIA? And, is social inclusion an appropriate, or useful, concept for those who work at the coalface of disadvantage?

To answer these questions, this study takes a policy-to-practice approach: examining changes in federal policy through to 'street-level' service delivery. In doing so, it aims to build a practical understanding of how the SIA will impact upon the not-for-profit sector and its ability to address disadvantage and promote social inclusion. The study is funded by the Australian National Health and Medical Research Council and the Sidney Myer Foundation. It received approval from the University of Melbourne School of Population Health Human Ethics Advisory Group.

Increasingly, studies of social policy implementation and welfare reform have used inductive case study approaches at the organizational level [15–19]. In the case of social services, this is viewed as a particularly appropriate and productive methodological turn [14, 15]. Emerging research in this area highlights the importance of examining whether and how written policies are "translated into operational realities", and the variations and permutations that occur during this process [20]: p145. This 'street-level' analysis addresses current gaps in our understanding of policies and how they work [20]. For example, it gives us a fuller picture of how policies such as the SIA are "produced and experienced in daily life" [20]: p145. Brodkin[20] argues that this approach is most valuable when policy implementation involves "change in organizational practice, discretion by frontline workers, and complex decision-making in a context of formal policy ambiguity and uncertainty" [20]: p145.

Lurie [18] has argued for the use of comparative case study methodologies for street-level analysis of welfare reform. Comparative case studies examine multiple cases within a shared framework, seeking out what is both common and particular, and examines the patterning of variables and relationships [21, 22]. However, the use of ethnographic techniques in this area is rare. While ethnography has gained increasing prominence in implementation and welfare studies, it has primarily been used to examine the experiences of clients rather than organizations [23].

The evidence on the social determinants of health has meant that public health practitioners are increasingly expected to operate outside the health sector and in partnership with other sectors. The importance of social policy to health therefore cannot be underestimated. However, before the impact of broad-scale social or public health policies such as the SIA can be assessed at the population level, we need to understand how they are produced and experienced in daily-life. To do this, studies must investigate the implementation process. This is consistent with methodological advances occurring in political science and social policy, which have emphasised the importance of investigating how, and if, policies are translated into operational realities.