Chief of staff: Anatomy of the role in eight charts

The chief of staff role has been growing in importance and popularity as the pressure on private and public sector leaders intensifies. Called upon to spearhead transformational change, navigate complex business dynamics, balance strategic and tactical priorities, and handle myriad additional tasks, CEOs and other senior executives need to ensure that their own offices function seamlessly. Enter the chief of staff (COS).

Over the past decade, we have had the privilege of convening hundreds of chiefs of staff at McKinsey’s Chief of Staff Forum. Through discussions with the participants, we have gained valuable insights on how to excel in the role. Since then, we have fielded numerous questions about the role’s responsibilities, qualifications, and tenure, including: What experience does a COS need? What responsibilities does the role entail? What future positions does the COS role prepare one for?

To develop an empirical picture of the COS role, we analyzed publicly available data on approximately 250 chiefs of staff who have served in the role within the past eight years. The group is almost evenly split between men and women, and its members have worked at roughly 300 organizations around the world. Our analysis suggests that COS career trajectories and responsibilities vary widely, but a few broad archetypes emerge.

Where do organizations find chief of staff candidates?

Nearly two-thirds of chiefs of staff are appointed from within their organizations, which reflects the value that principals place on a COS having deep institutional knowledge and strong internal networks so they can hit the ground running. This is especially true in large organizations: at companies with 50,000 or more employees, 80 percent of chiefs of staff are internal hires.

When organizations do hire externally, they typically look outside their industries, with more than three-quarters of those individuals coming from other sectors. This isn’t surprising given competitive concerns, but it also highlights the fact that many chiefs of staff use the role to pivot their career direction.

Our analysis shows comparable performance among internal and external hires. While organizational knowledge is valuable, other skills—such as the ability to influence, build relationships, and bring fresh perspectives—are just as important. For example, one COS who attended the forum worked toward the role within the company, while another joined the organization at the same time as the CEO; both have been highly successful in their posts.

More chiefs of staff come from within their organizations than from outside.

How much professional experience do chiefs of staff bring to the role?

The average COS has just over 12 years of work experience, moving into the role from a midlevel position such as senior manager. However, our data shows two career points when individuals most often take on the chief of staff position. The first is five to ten years in; these chiefs of staff tend to focus on administrative tasks, supporting corporate governance (such as tracking KPIs or preparing for board meetings), and managing projects run from the principal’s office. The second group are midcareer executives with ten to 20 years of experience (those in the 15- to 20-year cohort represent a significant share). Their roles tend to encompass a greater level of leadership, and they often serve as their principals’ proxies in discussions and decisions.

We also found that the larger an organization, the more years of experience senior executives’ chiefs of staff typically have. This goes hand in hand with larger companies favoring internal hires and reflects principals’ desire to work with chiefs of staff who understand internal ways of working and can navigate the complexities large organizations entail.

Most chiefs of staff assume the role early in their careers or midcareer.

What professional backgrounds do chiefs of staff have?

The most common training grounds for chiefs of staff are strategy and operations, with roughly half of the chiefs of staff in our sample coming from these functions. Since a COS often handles a wide range of tasks and projects, being well acquainted with how the business runs and able to dive into operational matters are valuable skills.

Strategy and operations are the most common functional backgrounds for chiefs of staff.

Which executives do chiefs of staff serve?

The role of the chief of staff to the CEO emerged in the latter half of the 20th century, inspired by precedents in the military and political spheres. In recent years, however, other senior executives in both public and private sectors have been hiring chiefs of staff to manage their offices’ operations. Approximately three-quarters of chiefs of staff in our sample support CEOs, while the rest serve other C-suite executives, regional managing directors, or board chairs. When multiple executives in an organization have chiefs of staff, their chiefs of staff tend to work together behind the scenes, share best practices, and coordinate on their principals’ shared priorities. A few organizations—including some of the world’s largest companies—have formal COS programs, with most senior-executive team members assigned chiefs of staff and individuals sometimes playing multiple COS roles during their careers at those companies.

Three-quarters of chiefs of staff serve organizations’ top leaders.

What other formal roles do chiefs of staff play?

The COS role is typically all-absorbing, so it’s no surprise that only 9 percent of our sample formally hold other positions in addition to their COS duties. Those who do “double hat” tend to have leadership roles (with head or senior-vice-president titles, for example) in strategy, operations, or transformations. Holding more than one role is more common toward the end of a chief of staff’s tenure, when the individual is balancing a move to a new role while continuing to support their principal.

Fewer than one in ten chiefs of staff hold multiple roles.

How long do chiefs of staff stay in the role?

Most chiefs of staff we studied served in the role for a fixed and relatively short term: their median tenure was 2.3 years, compared with 4.8 years for the average large-company CEO.¹ This implies that many chiefs of staff use the role as a springboard to other career opportunities and that the role’s intensity is hard to sustain over the long term. As a result, many principals rotate through several chiefs of staff during their leadership tenures. Given the short COS tenures, it is critical that the principals align with each new COS on the specific responsibilities.

Most chiefs of staff serve in the role for less than four years.

Where do chiefs of staff go next?

While a third of chiefs of staff switch companies and even industries when they take on the role, the majority of our sample doubled down on their new domains once they had made the leap: four out of five took new roles in the industry where they served as chiefs of staff, typically at the same company. Our research suggests that having had an unrivaled view from the top as a COS, these executives are uniquely well placed to identify the best opportunities within their organizations or broader industries.

Chiefs of staff tend to remain in their industries in future roles.

Does serving as a chief of staff provide a career boost?

A stint as a COS can accelerate an executive’s career: two-thirds were promoted after serving as chiefs of staff, while 18 percent used the role as a launching pad for lateral moves (some into a different industry or function). Only one in ten individuals in our sample moved directly into another COS position, although some did come back to the role later in their careers.

On average, chiefs of staff move up more than one level in the organization in their subsequent positions—a sizable advance given the typical COS tenure is only two years. Those with relatively brief work experience and tenure prior to being a COS tend to make the largest jumps, which seems to validate many principals’ prioritization of hiring young, high-potential talent over those with years of experience.

The chief of staff role often provides a career boost.

Our analysis suggests that while there is no one-size-fits-all route into the COS role, exit opportunities are varied and typically lead to more senior positions. The COS role itself is flexible in its parameters and able to accommodate both relatively junior and midcareer senior executives, making it a rich proving ground for future leadership ambitions.