How should district and school leaders improve education for students traditionally underserved by public education: by increasing control over teaching and curriculum, or by empowering groups of teachers to have more collective autonomy, responsibility, and opportunities for professional learning? The second approach--promoting multiple trajectories of learning among groups of teachers--has advantages, as well as some challenges, as a means of closing various achievement gaps. Sociocultural theory informed our research, as it helped us envision how people who work together create opportunities for the adaptation and learning of new practices while increasing the likelihood that individuals internalize new skills and ways of thinking. Through the analysis of a conversation among teachers about Vickie, an English Language Learner, we examine the larger context of a school's reforms. This analysis illustrates both the possibility and desirability of helping teachers engage in multiple and evolving types of teacher learning in order to succeed with students like Vickie. Closing the achievement gap likely will require more than just choosing the right intervention and implementing it with fidelity. Conceptualizing the work of closing the achievement gap as requiring multiple, ongoing trajectories of teacher learning suggests what teachers, administrators, and district leaders can do to: foster and influence trajectories of teacher learning, promote internalization of new approaches, and sustain teachers' efforts to close the achievement gap in an "exhausting and exhilarating process that never feels finished" (Ellen, English teacher, Mountain High School, report to faculty meeting, August 21, 2003). (Contains 2 figures.)