In addition to identifying and developing superior classroom teaching, the National Board for Professional Teaching Standards (NBPTS) certification process is intended to identify and cultivate teachers who are more engaged in their schools. Here the authors ask, "Does NBPTS certification affect the number of colleagues a teacher helps with instructional matters?" If so, this could enhance the influence of NBPTS-certified teachers and their contributions to their professional communities. Using sociometric data within 47 elementary schools from two states, the authors find that NBPTS-certified teachers were nominated more as providing help with instruction than non-NBPTS-certified teachers. From analyses using propensity score weighting, the authors then infer that NBPTS certification affects the number of colleagues a teacher helps with instructional matters. The authors then quantify the robustness of their inference in terms of internal and external validity, finding, for example, that any omitted confounding variable would have to have an impact six times larger than that of their strongest covariate to invalidate their inference. Therefore, the potential value added by NBPTS-certified teachers as help providers has policy and practice implications in an era when teacher leadership has risen to the fore as a critical force for school improvement. (Contains 3 figures, 4 tables, and 21 notes.)