Fundamentally, the relationship is similar to what you would find between ministers and their office staff on the political side and the professional non-partisan public service on the departmental side.
The Privy Council Office employees are part of the Public Service of Canada. We provide advice, based on evidence, to the Prime Minister and support the official duties of the Government of Canada. Official Government of Canada activities receive communications support through the Prime Minister's official website.
These distinctions between the role of public servants on the Privy Council side and political staff on the side of the Prime Minister's Office or in ministers' offices are defined and delineated in Open and Accountable Government, a guide provided to ministers and posted on the web.