In this paper we review the contribution of our original work titled "Simulating Instructional Roles Through Pedagogical Agents" published in the "International Journal of Artificial Intelligence and Education" (Baylor and Kim in "Computers and Human Behavior," 25(2), 450-457, 2005). Our original work operationalized three instructional roles as simulated through pedagogical agents, and demonstrated the effectiveness of these agent roles on learning and motivation. Since the publication of our work, pedagogical agent research has expanded its scope from the provision of intelligent guidance to a broad interest in agents' social and affective support for learners. We discuss current progress in pedagogical agent roles and capabilities, and speculate about the future of agent role design. We expect that optimizing the roles of artificial beings including on-screen agents and robots will continue to interest the educational technology community as these technologies continue to evolve.