The Resource Management Act defines kaitiakitanga as the exercise of guardianship by the tangata whenua of an area in accordance with tikanga Maori in relation to natural and physical resources, and includes the ethic of stewardship.

The role of kaitiaki has evolved to accommodate contemporary resource management processes. Under the Resource Management Act, the duties associated with kaitiakitanga include:

• Restoring and rehabilitating degraded mahinga kai sites
• Assessing the cultural implications of proposed developments, including through the preparation of cultural impact assessments
• Lodging submissions and presenting evidence on plan development processes and resource consent applications
• Forming constructive relationships with environmental agencies, such as councils, the Department of Conservation and Fish and Game

The outcomes of kaitiakitanga are likely to include avoiding the discharge of waste (particularly human waste) into rivers and lakes, the management of natural resources in a way that maintains mahinga kai values, and ensuring that all natural resources are available for future generations in as good, or better, quality than they currently exist.

To give effect to the concept of kaitiakitanga it is important to consult with the appropriate people. The Crown has a duty to consult with tangata whenua which arises out of the relationship of Treaty "partners".

Section 7(a) provides recognition that kaitiaki need to be provided with the opportunity to exercise guardianship of the natural and physical resources within their area of influence in accordance with tikanga Māori. For example, in Carter Holt Harvey Ltd v Te Runanga o Tuwharetoa ki Kawerau [2003] 2 NZLR 349 the High Court recognised the role of Tuwharetoa as kaitiaki of the Tarawera River and upheld a condition on a long-term discharge consent for the paper mill at Kawerau which required Carter Holt Harvey Ltd to consult with Tuwharetoa if any issues arose during the 21-year term of the consent .

This matter points to limiting the use of a particular resource so that it does not become overused and that there is an incentive for other underused resources to be developed. The avoidance of waste and the best use of resources are other aspects of efficiency.

The Environment Court has noted that efficient use of resources may mean a number of things in any single case:

In Unison One the Court held that "it is efficient to utilise wind – it is a waste to leave it unutilised – and also to continue production from the farm underneath it. We consider that it might equally be alleged that it is efficient to spend the money that would be needed to buy expensive wind turbines, to buy cheap coal and cheap coal-driven plants and pay any carbon tax… It is also efficient, in the sense of avoiding waste, not to reduce the area of outstanding natural landscapes".

The Court stated that it was “uncomfortable with a cherry-picking approach to efficiency” and endorsed an approach that “requires a consent authority to consider the use of all the relevant resources and preferably their benefits and costs”.

On appeal from that decision, the High Court determined that section 7(b) does not require consideration of alternative or a comprehensive cost-benefit analysis of the proposal. Furthermore, a project does not need to be "the best" project in terms of net benefit to satisfy the efficiency criterion in section 7(b) as the RMA does not impose an obligation on resource owners or managers to use the resource in a way that is deemed best by council or court, only in a way that falls within the purpose of sustainable management. Nor does section 7(b) require an applicant for a resource consent to prepare a comprehensive cost-benefit analysis of the proposal.

The Resource Management Act defines amenity values as those natural or physical qualities and characteristics of an area that contribute to people's appreciation of its pleasantness, aesthetic coherence, and cultural and recreational attributes.

The Resource Management Act does not require every proposal to maintain and enhance amenity values. The direction in section 5(c) to avoid, remedy or mitigate any adverse effects of activities on the environment clearly contemplates that activities may have adverse effects on amenity values and still be in accordance with the sustainable management purpose of the Act.

Note - section 6(b) is more relevant to amenity values associated with outstanding natural landscapes and outstanding natural features.

Section 2 of the RMA defines intrinsic values as “those aspects of ecosystems and their constituent parts which have value in their own right, including (a) their biological and genetic diversity, and, (b) the essential characteristics that determine an ecosystem’s integrity, form, functioning, and resilience.” This provision complements the objective in section 5(2)(b) of safeguarding the life-supporting capacity of ecosystems.

The general requirement to maintain and enhance the quality of the environment complements the environmental obligations contained within the definition of sustainable management (sections 5(2)(a), (b) and (c)). As described for section 7(c) above, there is no requirement for every proposal to maintain and enhance the quality of the environment, but this should be achieved overall.

This provision directs consideration to issues of allocation or use of resources which are finite in nature (such as freshwater).

This provision derives from the Water and Soil Conservation Act 1967 which protected both indigenous and introduced fisheries. Indigenous fish and their habitat are now protected under the Conservation Act 1987 and the freshwater fisheries regulations as well as under section 6(c) of the RMA. Section 7(h) carries on the protection for introduced fisheries.

Trout and Salmon are useful water quality indicators. There is a close correlation between the habitat requirements of trout and salmon and suitable water quality for public uses such as swimming.

The requirement to have particular regard to the effects of climate change is aimed at considering the effects of climate change on the application, rather than the effects of the application on climate change.

The Ministry for the Environment produces guidelines which local authorities should utilise when considering the effects of climate change.

The requirement to have particular regard to the benefits to be derived from the use and development of renewable energy avoids the need to re-litigate on a case-by-case basis the benefits of renewable energy over those projects which use non-renewable energy sources. Section 7(j) indicates a clear preference for renewable energy over non-renewable energy.

However, the adverse effects of renewable energy projects (such as effects of biodiversity and landscape values) still need to be assessed to determine if a renewable energy project can proceed. Not all renewable energy projects will be consistent with the purpose of sustainable management.