This thesis examines Indonesia's growing interest to play a more significant role at the regional and global levels in the post-authoritarian era particularly during the presidency of Susilo Bambang Yudhoyono (2004 - 2014) through the lens of role theory. Drawing on interviews with forty research participants, ranging from Indonesian government officials, parliamentarians, and other foreign policy actors, as well as an analysis of key documents, this thesis identifies four main national role conceptions that were conceptualised and enacted by the Yudhoyono administration. These overarching roles are a voice for developing countries, a regional leader, an advocate of democratic and human rights norms, and a bridge-builder. These four role conceptions are set against the backdrop of significant changes in the domestic political environment as well as the international system, which gave Indonesian foreign policymakers an opportunity to reconstruct Indonesia's role in the regional and global order. However, these roles are by no means stable given that they are constantly being negotiated and contested. I develop this argument in case studies of Indonesia's engagement in regional and global governance in four areas: (1) regional human rights governance; (2) global human rights governance; (3) regional trade governance; and (4) global trade governance. Through the analysis of Indonesia's engagement in governance initiatives at the regional and global levels, this thesis contributes to role theory literature by further developing the conceptualisation of domestic and international audiences. The analysis aims to unpack the state by incorporating insights from several bodies of literature ranging from ontological security to work on state transformation which arguably provides the student of role theory with a more nuanced understanding of the dynamics within the state in articulating its role conceptions. This endeavour is important in the context of Indonesia's democratic transition since the collapse of the authoritarian regime in 1998.