Policy work is resource intensive, especially the time-consuming effort to gather, analyse, and keep up with all the relevant research, data, trends, and emerging practice. A lot of this groundwork in many policy domains is common across jurisdictions and contexts, so similar work is repeated in similar ways by similar people in many different places, all building separate policy infrastructure to establish the same foundational evidence base.
Resource constrained publicly funded organisations have tended to shift effort and investment away from deep policy work, in favour of service delivery and commissioning. That has left a shrinking cohort of policy specialists doing more work, across bigger domains. Policy has also accelerated, with less time for groundwork before policy makers decide and act.
There is also more competition in the market for analysis and advice, and mountains of evidence to climb. In many domains, the pace of research is too fast for policy workers to keep up. Traditional ways of sharing effort, or at least insight, like interagency working groups and committees, are also resource intensive and slow moving. We have pooled public data assets, like the census, for centuries, but still treat other forms of policy work as cottage industries.
It is obviously inefficient for everyone working in the same policy domain, or on similar policy issues, to find their own way to the same evidence base. Even with cooperative relationships, organisations often end up duplicating foundational work like literature reviews and summaries of evidence that could easily be shared. With the few remaining policy specialists busy just maintaining their expertise, any really big or urgent policy issues tend to need additional external support.
When every organisation forges its own path to gather and process evidence that is available to all, there are bound to be gaps and inconsistencies. Those with smaller jurisdictions or budgets, or more pressing policy priorities, tend to do less, and lower quality, groundwork. This can lead to unwarranted, and inequitable, variation in policy design and outcomes.

Many non-government organisations draw on shared policy infrastructure provided by a peak body. Peak bodies make policy work more efficient and effective by giving everyone access to a common evidence base, from which to adapt or develop local solutions.
Peak bodies can do the work once, to a high standard, to benefit many. Work like summarising existing evidence, consulting stakeholders, primary research, developing practice guidance and training resources, and benchmarking outcomes are time-consuming, and need not be duplicated by every organisation.
With a big head start on what is relevant for everyone, local policy workers can focus on what is unique to their context and how best to address those needs.
When policy workers with similar interests duplicate effort doing a lot of similar groundwork, there is less time and energy left for policy adaptation and innovation to meet local needs and goals. By building shared policy infrastructure in a peak body, everyone can secure faster and lower-cost access to the same evidence base camp. From there, they can adjust and adapt as required to meet their own needs and goals.
Collaborative networks have many benefits, but are also time-consuming to maintain. By formalising and normalising a shared body of evidence, policy workers can improve quality and consistency across domains and communities, as well as saving time and money.
Working through a peak body, we can reach higher summits by starting at a shared evidence base camp.