The temptation is to compare Justin Trudeau’s Prime Minister’s Office with that of Stephen Harper. But the more interesting comparison is with the PMO of his father.

It was Pierre Trudeau who gave us the modern version of the PMO. Before he inherited power from Lester Pearson in 1968, the office consisted of about 40 staff members; the more influential among them were senior advisers without clear responsibilities. The elder Mr. Trudeau recoiled from what he considered a chaotic work environment, in which ministers made ad hoc decisions with little central oversight, and the prime minister himself often set policy on the fly. So he set about instilling structure – more than doubling the PMO’s size, and putting in place powerful officials with clear lines of responsibility they were not to cross.

The degree of regimentation in the offices of the prime ministers between the two Trudeaus has varied, and sometimes the dynamics have shifted even within a single mandate. Mr. Harper, for instance, had a more hierarchical office when Nigel Wright was his chief of staff, and a somewhat more fluid one at other times. But few of them can be accused of actively seeking out a casual and free-flowing backroom dynamic.

So it has been striking to hear some government insiders use the word “Pearsonian” to describe what Justin Trudeau is aiming for in his PMO.

That’s not to say he is about to turn the clock back to the 1960s, exactly. In fact, he is as much trying to stay in touch with the more fluid management practices of the Google era – something he also embraced during a pre-election rebuild and modernization of the Liberal Party that some insiders compared to launching a start-up.

In any event, he is pushing, harder than just about any prime minister since his father, for a less centralized and regimented, more open and collaborative decision-making process than Ottawa has been conditioned to expect. If it works, it will produce more innovative and well-considered policies than would otherwise be possible; if it fails, a lack of discipline could make things messy in a hurry.

With the PMO having reached roughly 100 members by the time he took over from Mr. Harper, it appears Mr. Trudeau will attempt to shrink it again – although by how much won’t be clear until hiring has been completed, early this year. More ambitious and fraught is an attempt at a mostly “flat,” non-hierarchical organizational structure for upper-level staff, facilitating the looser, more free-flowing working culture.

Much has been made – with plenty of cocked eyebrows – about Mr. Trudeau’s pledge to re-empower cabinet, giving ministers greater control over what they say in public and how they steer their files in private than was the case under Mr. Harper in particular.

Less noticed has been the attempt at fluidity within the PMO itself.

There are still a couple of staffers at the top of the food chain, but even their roles are not that clear-cut. A common assumption in Ottawa is that principal secretary Gerald Butts is in charge of policy and communications strategy, while chief of staff Katie Telford runs operations (i.e. makes sure things actually get done). That’s true, up to a point. But there are few boundaries to delineate their roles. No significant decisions – about policy implementation or responses to emerging issues, or the contents of Mr. Trudeau’s speeches – are made without both weighing in.

Nor, it appears, are they usually made without quite a few other people weighing in as well. Mr. Trudeau is known to favour big, collaborative discussions that include other staffers, speaking as freely as Ms. Telford and Mr. Butts, encouraged to challenge their bosses and each other. There has been little ranking of those staffers within the PMO, and they are not limited to participating only in discussions that fall directly within their mandates. With an aim to create a less formal atmosphere, work spaces have been loosened up with more couches and other furniture supposed to encourage relatively relaxed conversations, between staffers and, in some cases, involving the PM himself.

Among the reasons many leaders avoid hearing from lots of internal voices on every issue is the potential for paralysis. Paul Martin, who tried during his brief time as prime minister to have a large group of staffers argue out decisions in front of him, was so notorious for being unable to sort through all the advice that The Economist branded him Mr. Dithers. U.S. President Barack Obama, particularly in his first term, was frequently accused of wasting time and political capital trying to litigate every issue behind the scenes.

Mr. Trudeau, who, in contrast to his much chillier father, is as affable and eager to please a prime minister as this country has seen, could well be susceptible to such pitfalls. Cynics suggest he will ultimately just turn to Mr. Butts for a final call. Among insiders, the more common response – beyond Mr. Trudeau being capable of running a solid meeting, separating good advice from bad, then making a decision and sticking with it – boils down to his staff having great chemistry and being less prone to competition than most. (Or, as one senior Liberal put it, “We have a strict ‘no asshole’ rule.”)

For now, the fairest criticism of Mr. Trudeau’s PMO may be that, for all its fluidity and camaraderie, too many senior staffers come from the same small world. Considerably less diverse than Mr. Trudeau’s cabinet, they are disproportionately from Ontario, with nearly half the upper ranks – including Ms. Telford and Mr. Butts – having cut their teeth at Queen’s Park. Most played significant roles on his campaign. Although they may offer different takes on individual issues, there are few indications yet that many of them have dramatically different worldviews; moderately left-of-centre pragmatic activism seems to rule.

As some of this crowd exits and replacements step in, as is likely to happen even before Mr. Trudeau has finished serving a single term, the turf protection and regimentation that came to plague the offices of his predecessors may return.

But for now, with the upper ranks of this new PMO set, there are a dozen key people helping Mr. Trudeau chart the course of his new government.

Adam Radwanski writes on national politics for The Globe and Mail.