While many efforts to foster teacher leadership focus on the power, authority, and control that can come with teachers' formal positions in organizational hierarchies, case studies of 4 teachers document how expertise, credibility, and influence can come together in teachers' activities regardless of the formal positions they hold. These teachers' expertise emerged from investigations of issues that were of concern to them in their own classrooms and schools. Through these investigations, they developed representations that both helped them to articulate their own ideas and facilitated the sharing of their work in a variety of different contexts. The connections these teachers made provided them with new perspectives, helped them to build their credibility, and enabled them to gain access to individuals who served as translators, advocates, and amplifiers for their work. Despite conditions that provided little support for and often significant discouragement from sharing their work and ideas, their experiences suggest some of the ways that schools, school systems, and reform networks can build on the ideas, energy, and influence of teachers both in the classroom and out.