In the main, this research work reviews the most important historical milestones in matters of religious freedom; raises and elucidates conceptual questions (delimitation of the idea of? religion?); assumes a human rights perspective based on applicable human rights treaties; examines the limits to state power in matters of controversies related to conscience; studies the consequences of the position that demands a state neutrality in religious matters; and analyzes the degree of autonomy of religious associations regarding possible conflicts with other rights. The methodological approach is generally focused on the analysis of national and comparative jurisprudential decisions, but without neglecting the theoretical support: the thesis presupposes a liberal democratic view and concludes that religious freedom, rather than an isolated and special statement, results from a combination of other freedoms and rights, such as association, privacy, expression, among others. The work is an original and relevant contribution, and an unavoidable text for the study of the important and urgent problems it addresses.