To be included on the World Heritage List, sites must be of outstanding universal value and meet at least one out of ten selection criteria. These criteria are explained in the Operational Guidelines for the Implementation of the World Heritage Convention which, besides the text of the Convention, is the main working tool on World Heritage. The criteria are regularly revised by the Committee to reflect the evolution of the World Heritage concept itself.

Until the end of 2004, World Heritage sites were selected on the basis of six cultural and four natural criteria. With the adoption of the revised Operational Guidelines for the Implementation of the World Heritage Convention, only one set of ten criteria exists.

Selection criteria:

1. to represent a masterpiece of human creative genius;
2. to
   exhibit an important interchange of human values, over a span of time
   or within a cultural area of the world, on developments in architecture
   or technology, monumental arts, town-planning or landscape design;
3. to
   bear a unique or at least exceptional testimony to a cultural tradition
   or to a civilization which is living or which has disappeared;
4. to
   be an outstanding example of a type of building, architectural or
   technological ensemble or landscape which illustrates (a) significant
   stage(s) in human history;
5. to be an outstanding example of a
   traditional human settlement, land-use, or sea-use which is
   representative of a culture (or cultures), or human interaction with
   the environment especially when it has become vulnerable under the
   impact of irreversible change;
6. to be directly or tangibly
   associated with events or living traditions, with ideas, or with
   beliefs, with artistic and literary works of outstanding universal
   significance. (The Committee considers that this criterion should
   preferably be used in conjunction with other criteria);
7. to contain superlative natural phenomena or areas of exceptional natural beauty and aesthetic importance;
8. to
   be outstanding examples representing major stages of earth's history,
   including the record of life, significant on-going geological processes
   in the development of landforms, or significant geomorphic or
   physiographic features;
9. to be outstanding examples
   representing significant on-going ecological and biological processes
   in the evolution and development of terrestrial, fresh water, coastal
   and marine ecosystems and communities of plants and animals;
10. to
    contain the most important and significant natural habitats for in-situ
    conservation of biological diversity, including those containing
    threatened species of outstanding universal value from the point of
    view of science or conservation.

The protection, management, authenticity and integrity of properties are also important considerations.

Since 1992 significant interactions between people and the natural environment have been recognized as cultural landscapes.

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