Species Survival Commission (SSC)
SSC advises the Union on the technical aspects of species conservation and mobilizes action for those species that are threatened with extinction. Members: 7000.
http://www.iucn.org/about/work/programmes/species/about_ssc/index.cfm

World Commission on Protected Areas (WCPA)
WCPA promotes the establishment and effective management of a worldwide representative network of terrestrial and marine protected areas. Members: 1300.
http://www.iucn.org/about/union/commissions/wcpa/index.cfm

Commission on Environmental Law (CEL)
CEL advances environmental law by developing new legal concepts and instruments, and by building the capacity of societies to employ environmental law for conservation and sustainable development. Members: 800.
http://www.iucn.org/about/union/commissions/cel/index.cfm

Commission on Education and Communication (CEC)
CEC champions the strategic use of communication and education to empower and educate stakeholders for the sustainable use of natural resources. Members: 600.
http://www.iucn.org/about/union/commissions/cec/index.cfm

Commission on Environmental, Economic and Social Policy (CEESP)
CEESP provides expertise and policy advice on economic and social factors for the conservation and sustainable use of biological diversity. Members: 500.
http://www.iucn.org/about/union/commissions/ceesp/index.cfm

Commission on Ecosystem Management (CEM)
CEM provides expert guidance on integrated ecosystem approaches to the management of natural and modified ecosystems. Members: 400.
http://www.iucn.org/about/union/commissions/cem/index.cfm