The opponents believe that the consequence of water being a human right excludes private sector involvement and requires that water should be given to all people because it is essential to life. Access to water as a human right is used by some NGOs as a means to combat privatization efforts. A human right to water "generally rests on two justifications: the non-substitutability of drinking water ("essential for life"), and the fact that many other human rights which are explicitly recognized in the UN Conventions are predicated upon an (assumed) availability of water (e.g. the right to food)."