The smaller number of MPAs compared to terrestrial protected areas means there is less experience and understanding of applying categories to MPAs. Application of the categories to MPAs has often been inaccurate and inconsistent. These supplementary marine guidelines are therefore aimed at ensuring that the IUCN categories can be effectively applied to all types of MPAs, as well as to any marine components of adjoining terrestrial protected areas, provided a site meets the IUCN definition of a protected area.
Inconsistencies in the application of, and reporting on, the categories reduce the efficacy and use of the system as a global classification scheme. These guidelines are geared towards solving this problem by increasing the accuracy and consistency of both assignment and reporting. The categories are recognized by international bodies such as the United Nations and by many national governments as the global standard for defining and recording protected areas, and as such are increasingly being incorporated into legislation. Further information on these international conservation initiatives is found in Chapter 7 of the 2008 Guidelines.
The guidelines are intended primarily for policy makers, decision makers, senior managers, agencies and other institutions involved in the establishment and management of MPAs. They will also be useful for MPA managers, as a category to which an MPA has been assigned can help a manager understand the management objectives and thus guide planning and implementation. The guidelines will also benefit those involved in collecting, analyzing and reporting data on MPAs.