The Three Functions of a Chief of Staff
I've been a Chief of Staff several times over, and I worked at a company that had hundreds of them. After enough cycles, a pattern became impossible to ignore: the role was nominally the same job, and the people doing it were not even close to doing the same work. Some were running their executives' shops with quiet rigor — I came to call them strategic operators. Some were substituting for their executives surreptitiously — shadow executives. Some were glorified assistants no one had bothered to redirect.
I found myself trying to learn from the strategic operators. They were doing something that looked, from the outside, almost invisible. They weren't running things. They weren't deciding things. They were making it possible for their executive to do both better than the executive could have alone.
The framework on this page is what I built to name what I was seeing. I've used it to evaluate what kind of CoS I was at any given moment, what kind of CoS a peer was being, and (increasingly) what kind of CoS a hiring manager was actually looking for when they wrote a job description.
It's most useful as a diagnostic. If you're hiring a CoS, this is what to look for and what to screen against. If you're a CoS yourself, this is a way to read your own work. If you're an executive trying to scope the role, this is what you're choosing between when you say "I need a Chief of Staff."
What the role actually does, when it's done well.
01Operational Lead
The CoS owns the executive's operating cadence. At a tactical level, this is calendar logic, briefing flows, agenda construction, and follow-through on decisions made in the room. At a strategic level, it's the design of the executive's signature moments — QBRs, leadership offsites, all-hands events, board-prep cycles — and the operating rhythm that connects them. The work is unglamorous and high-leverage. Done well, it's invisible. Done badly, the executive's calendar runs the executive instead of the other way around.
The most concrete example I can give from my own work is the COVID briefing cadence I ran for an SVP whose 18,000-person organization moved to fully remote operations in 11 days. Two daily standups at the start, compressed to one within weeks, then weekly as the system stabilized. Each standup ran on a fixed structure: status from the VP whose phase was active, two or three decisions surfaced for the SVP, blockers escalated by name. The cadence is what made the timeline possible. Without it, every decision would have routed through the SVP's inbox or one-off meetings.
02Trusted Advisor
The CoS sits between the executive and the executive's direct reports as a smoothing function. At a tactical level, this is owning the staff meeting agenda, tracking actions, and making sure decisions made in the room actually land. At a strategic level, it's something more delicate: serving as an intermediary across VPs when there's friction the executive shouldn't have to broker, redesigning the operating cadences between functions when the cadences are producing dysfunction rather than solving for it, and translating the executive's priorities into work the VP layer can actually execute.
The example I'd point to here is the OV (Operational View) process I built between workforce planning and finance during my time as Associate Director, Workforce Strategy. Workforce and finance had a famously adversarial relationship: workforce wanted to stay true to the model, finance wanted to stay true to the budget, and meetings between them tended to bombard the SVP with unrehearsed disagreement. I redesigned the cadence: hard exchange dates, pre-endorsed narratives, disagreements surfaced openly as discussion items rather than ambushes. The conflict between the two functions didn't disappear, but the SVP stopped being the venue where it played out. That's Trusted Advisor work.
03Strategic Partner
The CoS owns a piece of the executive's legacy work — a project, an initiative, or a reputational frame the executive needs but cannot personally drive without losing focus on the rest of the role. There is no junior version of this. A glorified assistant doesn't get trusted with it. A shadow executive doesn't want to go near it. Only a strategic operator can do this function. The test of whether you're operating at this level is whether the executive has explicitly endorsed your move, and whether it's into a space no individual VP is positioned to own (but all would benefit from).
The example here is the Get Healthy campaign I led for my SVP toward the end of my CoS tenure. Her legacy ambition was to reposition customer service from a cost center to a value center — to refuse the framing that customer service should absorb cuts whenever the revenue side of the business underperformed. The campaign was operational on its surface: efficiency targets, AI-driven forecasting, lean staffing models. But the strategic intent was reputational. The customer service organization became the only operational bright spot in one of Verizon's worst financial quarters on record, and the SVP's standing in the C-suite strengthened materially through that period. The work was mine in the sense that I drove it sink-or-swim. The strategic vision behind it was hers. That's the line.
Three functions, three operators, nine cells.
The cells are diagnostic. Read across a row to see how the same operator type behaves across functions. Read down a column to see how each operator type performs the same function differently. The Strategic Operator row is shaded because it's the row hiring managers usually mean when they say "Chief of Staff."
The hardest distinction to read from the outside.
The most important distinction in the matrix is the one between Strategic Operator and Shadow Executive at the Trusted Advisor row, because that's where the two are hardest to tell apart in practice.
Both versions involve the CoS sitting between the executive and the VP layer. Both involve managing information flow. Both involve relationships across the leadership team that the executive doesn't have the bandwidth to maintain personally. The difference isn't visible in the activity. It's visible in the direction of the work.
A Strategic Operator uses the CoS access to make the executive better: more informed, faster on decisions, less burdened by friction the VP layer can resolve among themselves with the right cadence. A Shadow Executive uses the same access to make themselves better positioned: for promotion, for alliance-building, for political capital they were never authorized to spend. The activity looks identical from the outside. The motivational signature is the only reliable diagnostic.
The consequences of getting this wrong usually arrive late, but they always arrive — in the form of an executive transition that exposes the CoS as having been freelancing, a VP relationship that surfaces as broken at the worst possible moment, or a next-role search where everyone in the previous executive's network quietly declines to take the call. The role rewards restraint at a level most other senior roles don't. That's the part most CoSes haven't articulated, and it's the part I've watched separate the careers that compound from the ones that stall.
If you're hiring for the role, the question to ask isn't "can this person be a Chief of Staff." It's "which version of the role are they going to be, and which version do you actually want."