Since independence, the small island state of Singapore has been dependent on its human resource to support economic growth and sustainability. Hence, there is a need for high investment in developing quality workforce with relevant competencies to compete in the global market space. Quality workforce, however, is dependent on quality education, and specifically, quality teachers to produce quality student learning outcomes. Investment in teacher professional learning is therefore important to sustain a quality teaching force to sustain the tight coupling between education and economy. Investment in teacher professional learning is evident in the developments of professional learning that have taken place since 1997 including the formation of the Teachers Network, and then the Academy of Singapore Teachers, along with the establishment of school- and system-wide teacher inquiry tools such as action research and lesson study via teacher learning communities (e.g., professional learning communities, networked learning communities). Underlying these developments is the importance of teacher agency and teacher collective agency embedded and integrated in their professional work and learning, along with the education policies and initiatives, notwithstanding the counter prevailing challenges.