Carnegie researcher Paul LeMahieu and his colleagues have summarized these six principles as "three interdependent, overlapping, and highly recursive aspects of improvement work: problem definition, analysis and specification; iterative prototyping and testing...; and organizing as networks to...spread learning". Professional learning communities (PLCs) are increasing in popularity in education to promote problem solving and often align with many of these design principles. Researcher Anthony Bryk sees PLCs as a place to begin applying these principles, but also notes that PLC success is often isolated by teams or within schools and remains heavily dependent on the individual educators involved. A mechanism is needed to accumulate, detail, test, redesign knowledge in partnerships like PLCs so that it can be transformed and transferred as collective professional knowledge across diverse and complex settings.