Outcome Mapping is a planning, monitoring, and evaluation methodology focused on changes in behavior of social actors that a project works with, rather than attributing overall impact. It was developed by IDRC in response to issues with traditional approaches. Key aspects include focusing on a project's sphere of influence, defining expected, desired, and ideal changes ("progress markers") for "boundary partners", and monitoring efforts to contribute to those changes through non-linear social change. The methodology aims to better understand a project's role in development by assessing influence on partners, rather than direct attribution of overall impact.