Many New Zealanders take access to safe drinking-water for granted, yet approximately 20 percent of Aotearoa New Zealand’s population is supplied with water that does not comply with drinking-water standards. Non-compliant drinking-water supplies place communities at increased risk of contracting waterborne pathogens such as hepatitis A, Campylobacter and Giardia (Ministry of Health, 2013). These pathogens contribute significantly to the burden of illness in rural communities. For example, monitoring undertaken by Northland Health (Project Waiora) in the late 1990s found persistent faecal coliform (Escherichia coli) transgressions in many Northland schools and marae (Auckland Regional Public Health Service, 2005). In 1998 a hepatitis A outbreak at a Hokianga marae, caused by contaminated drinking-water, required the vaccination of 800 people (New Zealand Public Health Report, 1999). Despite the urgent public health need, no action was taken. There are several possible reasons for this: a lack of drinking-water treatment expertise in the local public health unit; safe drinking-water not being accorded priority, or funding by the Ministry of Health, due to its non-regulated nature (Mistry, 2012); a lack of political will to remedy the situation; and/or funding constraints being used to justify inaction (Jellie et al., 2003). For Hokianga hapū (sub-tribes), access to safe drinking-water is a community priority. A clean and healthy environment, and the ability to fulfill kaitiaki (environmental stewardship) responsibilities, is critical to whānau, hapū and iwi (family, sub-tribe and tribe) identity and wellbeing. For the past two decades, in the face of local authority inaction, local health provider Hokianga Health Enterprise Trust (HHET)/Hauora Hokianga has supported (ultimately successful) hapū efforts to improve community drinking-water supplies. These developments have shaped public policy, environmental health practice and understanding of community development throughout the country. In this chapter the case of small water-supply management in the Hokianga region will be explored, firstly to demonstrate the ways in which policy can be utilised by communities for gains unforeseen by policy-makers, and secondly to offer insights into the social policy/social work interface.