The research community distinguishes between types of research based on the purposes for which it is conducted. The process research favored by educators in Reggio Emilia promotes reflective practice and program improvement through formative methods that help educators to better understand the context of their problems, assess the needs and responses of their stakeholders, and analyze "what works and what does not" on an ongoing basis. However, although such research assists educators while programs are ongoing to refine and improve their work, it does not allow outside audiences to understand outcomes and measure impacts over time. While we have some research on Montessori education, some policy makers continue to ask for new studies of Waldorf and Reggio Emilia schools that would measure lasting child-related outcomes and evaluate program quality based on external criteria. As discussed above, educators in dialogue with Reggio Emilia strongly question the validity and usefulness of such research (Dahlberg, Moss, & Pence, 1999).