At the outset, it is important to highlight that the vast majority of counterterrorism measures are adopted on the basis of ordinary legislation. In a limited set of exceptional national circumstances, some restrictions on the enjoyment of certain human rights may be permissible. Ensuring both the promotion and protection of human rights and effective counter-terrorism measures nonetheless raises serious practical challenges for States. One such example is the dilemma faced by States in protecting intelligence sources, which may require limiting the disclosure of evidence at hearings related to terrorism, while at the same time respecting the right to a fair trial and the right to a fair hearing for the individual. These challenges are not insurmountable. States can effectively meet their obligations under international law by using the flexibilities built into the international human rights law framework. Human rights law allows for limitations on certain rights and, in a very limited set of exceptional circumstances, for derogations from certain human rights provisions. These two types of restrictions are specifically conceived to provide States with the necessary flexibility to deal with exceptional circumstances, while at the same time—provided a number of conditions are fulfilled—complying with their obligations under international human rights law. 1.  Limitations As provided for by international human rights conventions, States may legitimately limit the exercise of certain rights, including the right to freedom of expression, the right to freedom of association and assembly, the right to freedom of movement and the right to respect for one’s private and family life. In order to fully respect their human rights obligations while imposing such limitations, States must respect a number of conditions.33 In addition to respecting the principles of equality and non-discrimination, the limitations must be prescribed by law, in pursuance of one or more specific legitimate purposes and “necessary in a democratic society.” (a)  Prescription by law Common to international, regional and domestic human rights instruments and guidelines is the requirement that any measure restricting the enjoyment of rights and freedoms must be set out within, or authorized by, a prescription of law.34 To be “prescribed by law”: (a) the law must be adequately accessible so that individuals have an adequate indication 23