This thesis considers the scope and application of the human right to freedom of conscience. It traces the development of the right to conscience in international law, analyses the principal human rights treaties which codify the right, and considers various interpretations of the right to conscience in select national courts. The thesis argues that in judicial and scholarly interpretation, the human right to freedom of conscience has been linked too closely to religious belief, thus obscuring the non-religious dimensions of the right. The thesis aims to develop a jurisprudential framework to facilitate a broader practical application of the right to conscience. Developing an analysis of the scope of the right to conscience, the thesis considers two distinct aspects: first, the forum internum, relating to the right to harbour a conscientious belief internally, and second, the forum externum, relating to the right to externally manifest a conscientious belief. Building upon this scheme, the argument turns to three practical applications of the right to conscience: conscientious objection to military service, objection to certain types of state taxation on conscientious grounds, and objection to the performance of a termination of pregnancy. For each example, the international and national aspects are considered. The thesis concludes that a more generous scope be accorded to the right to conscience and more rigorous analysis be utilised when considering the application of the right.