Freedom of peaceful assembly is a recognized right under international human rights law. This report provides a comparative review of one aspect of this right: whether advance notification or authorization is required for an assembly to take place under the law of France, Italy, Portugal, Spain, Sweden, the United Kingdom, and the United States. The report also reviews the relevant case law of the European Court of Human Rights (ECHR).Article 11 of the European Convention on Human Rights and Fundamental Freedoms protects the right to peacefully assemble, but that right is not absolute; state authorities are given "a margin of appreciation" and may impose certain restrictions on the exercise of this right, provided that such limitations are (a) prescribed by law; (b) necessary in a democratic society; and (c) in the interests of national security or public safety, for the prevention of disorder or crime, for the protection of health or morals, or for the protection of the rights and freedoms of others. Similarly, in the United States, restrictions related to time, manner, and place imposed by government authorities can be justified as long as they are content-neutral, narrowly tailored to serve significant government interests, and leave other lines of communication open.