A/HRC/6/5 page 9 (c) Religious symbols 14. The concepts of worship, observance and practice of religion or belief extend to the display of symbols and they may also include customs such as the wearing of distinctive clothing or head coverings. The activities of the mandate have revealed two distinct issues of concern in this regard. On the one hand, many believers in various parts of the world are prevented from identifying themselves through the display of religious symbols, while on the other hand people in other countries are required to display religious symbols in public. The fundamental objective should be to safeguard both the positive freedom of religion or belief by voluntarily displaying religious symbols, and also the negative freedom from being forced to display religious symbols. In her 2006 annual report, the Special Rapporteur has formulated a set of general criteria, including “neutral indicators” and “aggravating indicators”, in order to evaluate - from a human rights law perspective - legislative and administrative actions which restrict or prohibit the display of religious symbols (E/CN.4/2006/5, paras. 51-60). (d) Observance of holidays and days of rest 15. The freedom to observe days of rest and to celebrate holidays and ceremonies in accordance with the precepts of one’s religion or belief is particularly significant since it allows believers to perform a series of ceremonies and religious customs that often have spiritual connotations. With regard to the situation in several countries, the Special Rapporteur has noted a number of good examples of legislation granting recognition to the religious holidays of various communities, allowing exemptions on religious grounds in schools or guaranteeing the right to conscientious objection for reasons of belief. Furthermore, religious holidays are often an opportunity to invite the leaders of other communities and get to know them, their cultures and their religions, as well as to promote interfaith dialogue. (e) Appointing clergy 16. The right to freedom of thought, conscience, religion or belief also includes the freedom to train, appoint, elect or designate by succession appropriate leaders. Religious communities have varied hierarchical structures and different approaches in designating their leaders. Undue interference in the training of religious leaders can lead to a shortage of appropriate leaders. Furthermore, some States encroach on the appointment procedure of religious leaders or require approval by the authorities for certain promotions within religious groups. The Special Rapporteur would like to emphasize that the freedom of religion or belief also protects the conduct by religious groups of their basic affairs, such as the freedom to choose their religious leaders, priests and teachers. (f) Teaching and disseminating materials (including missionary activity) 17. The question of missionary activities and other forms of propagating one’s religion has been at the centre of the mandate on freedom of religion or belief since its inception in 1986. Many communications sent by the mandate-holders pertain to alleged infringements of the right to write, issue and disseminate relevant publications or to teach a religion or belief in places suitable for these purposes. Pertinent examples include censorship, bans, confiscation and destruction of religious literature, even though these materials did not advocate national, racial or