This text comes to the conclusion that ""eventually freedom of thought, conscience and religion or belief may be the best instrument against a world governed by sheer materialistic forces: it is now more than ever relevant to protect and encourage further development of man's conscience"". This conclusion is reached on the basis of an extensive analysis of almost 50 years of UN debates concerning both the codification of this freedom and states' practices in this regard. The text analyzes in detail various elements of the freedom of thought, conscience and religion: individual aspects, the fight against discrimination based on religion or belief, collective aspects and promotion of tolerance in matters relating to religion or belief. The analysis shows the extent to which these freedoms and rights have been recognized, and their limitations. The main focus of the text is on the United Nations and a short survey of developments in various European instruments has also been included.