Any European cancer center/institute, organisation (including those composed by two or more members), legal entity or natural person, active in the area of cancer, including prevention, research, care, rehabilitation, provision of services and which fulfils the conditions as in Article 4 of EEC Regulation 2137/85, may become Member of the Grouping (hereinafter called a "Member").

The Members are diveided into the following 3 categories (as defined in the preamble):

• The “Cancer Centre Members”;
• The “Industrial Members” and
• The “National Cancer Networks”.

Each Member holds a share without nominal value and is jointly and unlimitedly liable for any debt incurred by the Grouping.