The concept of remedies has always been an important component of the legal system. Throughout the world, countries have utilized environmental law in a variety of ways to legislate for the remediation and rehabilitation of destroyed or degraded land and ecosystems. For example, in some countries, environmental law has provided for the remediation of contaminated mine sites, which can rather be classified as environmental restoration. However, often these countries have yet to properly enforce such law. Furthermore, given the significant increase in anthropogenic harm during the past few decades, there is an increasing realization that more needs to be done than simply acting to protect an environment from harm. Unlike the terms “rehabilitation” and “remediation,” the term “restoration” is drawn from the science of restoration ecology. The Society for Ecological Restoration (SER) defines ecological restoration as “the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed.” Ecological restoration contributes to the application of the ecosystem approach. There are different approaches to ecological and ecosystem recovery, such as rewilding or extreme forms of restoration such as “de-extinction.” This is due to the inherent complexity of assisting nature to recover from anthropogenic harm. Ecological restoration is the most prominent practice among ecologists to restore ecosystems, but is not the only approach. The main focus here will be on ecosystem restoration. “Restoration ecology” is the broad name for the scientific discipline behind ecological restoration and other recovery initiatives, and is a relatively new but rapidly developing branch within the study of natural sciences. Even more recently, there has been increasing legal attention to ecological restoration. There is no separate instrument in international law dealing with ecological restoration. However, legal obligations for restoration can be found in various multilateral environmental agreements, regional conventions, regional instruments such as European Union (EU) directives, and soft law instruments. The 1992 Convention on Biological Diversity (Biodiversity Convention) is an important convention outlining State party obligations for ecological restoration, as can be seen in both the Convention text and subsequent Conference of Parties decisions, including the 2010 Aichi Targets, which detail a specific target for ecological restoration. Prior to the Biodiversity Convention, the international community utilized the 1971 Ramsar Convention on Wetlands of International Importance especially as Waterfowl Habitat (Ramsar Convention) to introduce the concept of restoration. Other conventions that address ecological restoration or species restoration include the 1972 UNESCO Convention Concerning the Protection of the World Cultural and Natural Heritage (World Heritage Convention), the 1979 Bonn Convention on the Conservation of Migratory Species of Wild Animals (Convention on Migratory Species), and several of its additional agreements. Climate change poses both opportunities and additional challenges for restoration. Restoring ecosystems such as forests and peatlands assists in the reduction of carbon in the atmosphere. Within the framework of the United Nations Framework Convention on Climate Change (UNFCCC 1992) and the 2015 Paris Agreement, the role of restoration has been recognized. As various conventions and soft law instruments now impress obligations of restoration, the legal duty to restore the environment has matured into a customary obligation and can be considered as an emerging legal principle. However, most instruments containing legal obligations for restoration do not contain a clear definition or further clarification on how a State party might restore an ecosystem.