This study examines differences in how international regimes for the establishment and management of protected areas have been implemented in Norway and in Sweden. We focus on regulatory and normative pathways of international influence, which mirror the distinction between legal and non-legal regimes in international environmental law. Sweden and Norway have essentially responded similarly to the regulatory regimes that apply to both countries. The more normative regimes have influenced them in different ways -- primarily by strengthening traditional nature conservation norms in Sweden, and norms about sustainable use by local communities in Norway. The findings indicate that the normative pathway is important mainly as a support for domestic policies that correspond with existing national norms and discourses, and they support the proposition that a high degree of regulatory hardness contributes to increase the level and consistency of implementation.