Environmental factors impact on the enjoyment of human rights in a number of ways. However, the exact nature of the relationship between the environment and human rights in international human rights law remains unsettled, most notably in relation to the concept of a human right to a good environment. While the idea of a substantive right to an environment of a particular quality has received considerable support, it has yet to be adopted in any international legal instrument and remains the subject of much debate. This thesis interrogates the concept of a right to a good environment from a variety of perspectives to provide a comprehensive analysis of its suitability for inclusion in international human rights law. Given that climate change represents the biggest environmental challenge to have faced the international community, the thesis considers whether the right to a good environment is capable of providing new approaches for addressing the human rights implications of climate change. This thesis analyses the theoretical, legal, practical and political implications of the right to a good environment. It considers the theoretical foundations of human rights to assess whether the right is justifiable. It is concluded that a 'good environment' cannot be linked to human dignity, autonomy or interests without relying on rights which are already protected under existing law, such as the rights to health, food and water. It concludes that, without an independent justification, legal recognition of the right would risk undermining the existing human rights framework. The thesis also considers existing human rights approaches to environmental protection and to climate change in particular to determine whether a new right offers any significant practical benefits which might otherwise justify its recognition. The transnational, cumulative and ongoing impacts of climate change create significant challenges for enforcing human rights and it is argued that these effects would be even more problematic in relation to the right to a good environment. Because international legal recognition of new human rights depends on having the support of States, the thesis considers the current attitudes of States towards environmental human rights and human rights approaches to climate change. States are currently reluctant to acknowledge that they owe human rights obligations with respect to climate change and it is argued that they would be particularly unwilling to accept obligations under a new right to a good environment. Without the support of States, there is little likelihood that the right to a good environment would be adopted into international human rights law. The thesis concludes that continued proposals to recognise the right to a good environment in international law should be abandoned. The various theoretical, legal, practical and political considerations examined in the thesis indicate that it is not possible to settle on a definition of the right which would be both practically useful and independently justifiable. Further attention should instead be directed to clarifying the application of existing human rights law to environmental degradation, including the impacts of climate change.