Freedom of association encompasses both an individual's right to join or leave groups voluntarily, the right of the group to take collective action to pursue the interests of its members, and the right of an association to accept or decline membership based on certain criteria. "Freedom of Association, The Essentials of Human Rights" describes the right as coming together with other individuals to collectively express, promote, pursue and/or defend common interests. Freedom of Association is both an individual right and a collective right, guaranteed by all modern and democratic legal systems, including the United States Bill of Rights, article 11 of the European Convention on Human Rights, the Canadian Charter of Rights and Freedoms, and international law, including articles 20 and 23 of the Universal Declaration of Human Rights and article 22 of International Covenant on Civil and Political Rights. The Declaration on Fundamental Principles and Rights at Work by the International Labour Organization also ensures these rights.