The conservation status of a group of organisms (for instance, a species) indicates whether the group is still extant (that is, members of it are still alive) and how likely the group is to become extinct in the near future. Many factors are taken into account when assessing conservation status: not simply the number of individuals remaining, but the overall increase or decrease in the population over time, breeding success rates, known threats, and so on.
The IUCN Red List of Threatened Species is the best-known worldwide conservation status listing and ranking system. The system divides threatened species into three categories: Critically Endangered (CR), Endangered (EN), and Vulnerable (VU). Also listed are the documented extinctions that have occurred since AD 1500 and taxa that are extinct in the wild. Lower risk taxa are also divided into categories. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) aims to ensure that international trade in specimens of wild animals and plants does not threaten their survival.
In the European Union, the EU Wildlife Trade Regulation is legislation to provide for the implementation of CITES within the EU, and additional measures.
NatureServe conservation status focuses on Latin America, USA, Canada and the Caribbean, It has been developed over the past three decades by scientists from NatureServe, The Nature Conservancy, and the network of natural heritage programs and data centers. It is increasingly integrated with the IUCN Red List system. Its categories for species include: Presumed Extinct (GX), Possibly Extinct (GH), Critically Imperiled (G1), Imperiled (G2), Vulnerable (G3), Apparently Secure (G4), and Secure (G5). The system also allows ambiguous or uncertain ranks including inexact numeric ranks (e.g. G2?), and range ranks (e.g. G2G3) for when the exact rank is uncertain. NatureServe adds a qualifier for Captive or Cultivated Only (C), which has a similar meaning to the IUCN Red List Extinct in the Wild (EW) status
The Red Data Book of the Russian Federation is used within the Russian Federation, also accepted in parts of Africa.
- Australia. The Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) describes lists of threatened species, ecological communities and threatening processes. The categories resemble those of the 1994 IUCN Red List Categories & Criteria (version 2.3). Prior to the EPBC Act, a simpler classification system was used by the Endangered Species Protection Act 1992. State governments also have differing systems.
- Belgium. The Flemish Research Institute for Nature and Forest publishes an online set of more than 150 nature indicators in Dutch.
- Canada. COSEWIC (The Committee on the Status of Endangered Wildlife in Canada) is a committee of experts that assesses and designates which wild species are in some danger of disappearing from Canada Under the Species at Risk Act (SARA), it is up to the federal government, which is politically accountable, to legally protect species assessed by COSEWIC. See also: British Columbia Red List.
- China. The State, provinces and some counties have determined their key protected wildlife species. There is the China red data book.
- Finland. A large number of species are protected under the Nature Conservation Act, and through the EU Habitats Directive and EU Birds Directive.
- Germany. The Federal Agency for Nature Conservation publishes "red lists of endangered species".
- India. Wild Life Protection Act, 1972, Amended 2003 Biological Diversity Act, 2002
- Japan. The Ministry of Environment publishes a Threatened Wildlife of Japan Red Data Book.
- Netherlands. The Dutch Ministry of Agriculture, Nature and Food Quality publishes a list of threatened species, and conservation is enforced by the Nature Conservation Act 1998. Species are also protected through the Wild Birds and Habitats Directives.
- New Zealand. The Department of Conservation publishes the New Zealand Threat Classification System lists. Under this system threatened species or subspecies are assigned one of seven categories: Nationally Critical, Nationally Endangered, Nationally Vulnerable, Serious Decline, Gradual Decline, Sparse, or Range Restricted. While the classification looks only at a national level, many species are unique to New Zealand, and species which are secure overseas are noted as such.
- South Africa. The South African National Biodiversity Institute, established under the National Environmental Management: Biodiversity Act, 2004, is responsible for drawing up lists of affected species, and monitoring compliance with CITES decisions. It is envisaged that previously diverse Red lists (e.g. for mammals, birds, and plants) would be more easily kept current, both technically and financially.
- Thailand. The Wild Animal Reservation and Protection Act of BE 2535 defines fifteen reserved animal species and two classes of protected species, of which hunting, breeding, possession, and trade are prohibited or restricted by law. The National Park, Wildlife and Plant Conservation Department of the Ministry of Natural Resources and Environment is responsible for the regulation of these activities.
- Ukraine. The Ministry of Environment Protection maintains list of endangered species (divided into 7 categories from "0" - extinct to "VI" - rehabilitated) and publishes it in the Red Book of Ukraine.
- United States of America. The Endangered Species Act created the Endangered Species List.
Consumer guides for seafood, such as Seafood Watch, generally divide fish and other sea creatures into three categories, analogous to conservation status categories:
- Red ("say no" or "avoid")
- Yellow or orange ("think twice", "good alternatives" or "some concerns")
- Green ("best seafood choices").
The categories do not simply reflect the imperilment of individual species, but also consider the environmental impacts of how and where they are fished, such as through bycatch or ocean bottom trawlers. Often groups of species are assessed rather than individual species (e.g. squid, prawns).
The Marine Conservation Society has 5 levels of ratings for seafood species, as displayed on their Fishonline website.