Common Language is a shared way of thinking people can apply when considering how to improve the well-being of an individual child or group of children. It is sometimes described as an "operating system".
The Common Language method urges clarity about outcomes, risk, needs, threshold and activities. It requires that people interested in helping a child or children come together to decide what is needed, how much improvement in outcomes can be achieved, what outcomes to prioritize, how best to secure them and how to establish the effectiveness of their strategy. The approach strongly recommends experimental designs that randomly allocate eligible children to a new service or another condition.