With research findings indicating positive associations between teacher-child interaction quality and children's development and learning, many professional development efforts now focus on improving the ways in which teachers interact with children. Previous work found that MyTeachingPartner (MTP), a web-mediated coaching intervention, improved teachers' classroom interactions with children, and further analysis found that improvement in teachers' interactions was mediated by their responsiveness to the MTP intervention. The current study assessed how teacher characteristics, including demographics, beliefs, and psychological factors, as well as contextual characteristics related to multiple measures of teachers' responsiveness to MTP. Findings show that related factors vary across the different indicators of responsiveness. Specifically, the psychological factors of anxiety and readiness to change related to multiple indicators of responsiveness. Further, readiness to change and self-efficacious beliefs moderated the associations between classroom poverty and responsiveness. Study findings provide new insights into key teacher characteristics that might identify teachers in need of intervention adaptation or support to ultimately increase overall responsiveness. (author abstract)