Mentoring in companies around the world: case studies and outcomes of mentoring programs

For years mentoring has been used by organizations as a tool for employee development, knowledge transfer and building future leaders. Increasingly, however, companies no longer treat it merely as an additional employee perk. A well-designed mentoring program can be part of a talent management strategy, support onboarding, skills development, internal mobility and diversity and inclusion initiatives.

At Mentiway we have observed this in practice for years. We support organizations in designing and running mentoring programs, and we describe examples of our projects in a separate section Mentiway mentoring case studies. We have run over 100 mentoring programs and worked with thousands of participants, but due to confidentiality we cannot publicly discuss every engagement.

This time, therefore, we look at programs run by other organizations around the world. Not to prove that “mentoring always works,” but to examine what business goals companies try to achieve with it and what results they have actually been able to measure.

The compilation includes both large corporate programs and studies that allow mentoring to be viewed from a more scientific perspective.

Does mentoring really deliver results?

There is no single answer to that question, as much depends on how we define the effect of mentoring.

For one organization the most important metric will be the productivity of new hires. For another: the number of promotions among program participants, retention, the advancement of women into leadership positions, or faster onboarding of new staff.

Moreover, not every result reported by a company allows us to conclude that mentoring caused the change. If a company selects mostly high-potential employees for the program and then 70% of them get promoted, this does not automatically mean that 70% of the promotions were the result of mentoring.

Therefore, in the examples below it’s worth distinguishing between program outcomes and research findings, which allow for a much better assessment of causal relationships.

And one of the most interesting new examples shows that sometimes mentoring can deliver a very concrete business impact in just a few weeks.

1. Large sales organization: mentoring increased productivity by nearly 19%

One of the strongest pieces of evidence for the business value of mentoring comes from a study published in the journal Management Science in 2025. The researchers ran a field experiment in a large American sales organization, involving 591 newly hired employees across 52 cohorts.

This is an important example because it isn’t just a survey asking whether mentoring was helpful. Participants were randomly assigned to mentoring and non-mentoring groups, which allowed the researchers to assess the program’s actual impact far more accurately.

The process itself was fairly straightforward. Mentors were more experienced employees who were not the mentees’ managers. Pairs were asked to meet for 30 minutes a week for four weeks.

Result? In the group assigned to mandatory mentoring, daily sales revenue was about 19% higher, and revenue per handled call increased by about 12% compared with employees who did not receive a mentor. About 45% of the initial productivity gain persisted between the third and sixth months after the program ended.

Even more interestingly, the researchers also estimated the program’s economic value. For the 127 people assigned to mandatory mentoring, additional revenues over six months amounted to about $536,000, with program costs of $97,000. That translated to about $439,000 in net return above program costs.

This case, however, holds another important lesson for HR.

Should mentoring be voluntary?

In the same experiment the researchers compared mandatory and voluntary programs. And the result was surprising.

In the voluntary version, the effect of mentoring on productivity was close to zero. It turned out that the people who most often dropped out were also those who could have benefited most from the additional support. Their prior productivity was about 23-30% lower than that of the people who chose to participate.

This shows that simply opening recruitment for a mentoring program and waiting for people who “want to develop on their own” is not always the best solution.

It’s therefore worth designing the program not just around the question of who wants to be a mentee, but above all: who truly needs mentoring and what organizational problem it should address?

2. Principal Financial Group: 1,500 mentoring pairs in 17 countries

Mentoring can also work on a much larger scale.

Principal Financial Group launched a global mentoring program, whose first full year concluded with 1,500 mentoring pairs being matched across 17 countries. Members of the Executive Management Group also took part in the program.

The scale of the program is as interesting as the outcome. With a dozen or a few dozen pairs, organizers can still manage the process manually relatively easily. At 1,500 pairs, entirely different solutions are required: appropriate recruitment, matching, communication, monitoring, and tools to support participants.

Principal later also reported that people participating in the global mentoring program were about 50% less likely to leave the organization than those who did not take part.

This is a very interesting result from a retention perspective, but it should be interpreted with caution. It was not a randomized experiment, so we cannot conclude that mentoring on its own reduced turnover by 50%.

We can, however, say that participants in the program were significantly less likely to leave the organization. This is a good example showing that mentoring can be part of a strategy to build engagement and connection with the organization.

3. Two large companies in Poland: faster promotions and higher salaries

It’s also worth looking at data from the Polish market.

The study by Małgorzata Baran and Roland Zarzycki covered 392 employees of two large companies operating in Poland. Both organizations employed more than 1,000 people. Half of those surveyed participated in formal mentoring, and the other half did not take part in such a process.

Among other things, the researchers analyzed career trajectories and participants’ salaries. The results indicated that those who used mentoring achieved statistically significantly faster promotions than those in the non-mentored group. Their current salary levels were also higher.

This is a particularly interesting example for organizations that view mentoring as part of talent development and career path planning.

At the same time, the authors point to a limitation worth remembering when interpreting many mentoring studies: self-selection. More active, ambitious, and development-oriented people may be more likely to apply to mentoring programs and, at the same time, advance faster.

This does not mean that mentoring does not work. It simply means that when analyzing its effects you need to be careful not to attribute changes to mentoring that may also result from other factors.

4. pladis Türkiye: mentoring combined with talent management

Another interesting example shows what happens when mentoring does not operate as a separate HR initiative but is combined with a broader talent management process.

The company pladis Türkiye, known among others for the Ülker brand, formalized and digitized its internal mentoring program, linking it with its Talent Management processes.

In 2021 the program included 130 mentees and 83 mentors, and a year later 156 mentees and 84 mentors. According to data reported by the organization, the average performance rating of participants was 3.76, while the company-wide average was 3.39. The company also reported higher promotion rates among program participants.

This is an interesting example because it shows that mentoring can be used not only as a standalone development initiative but as part of a larger talent ecosystem.

At the same time, this is data reported by the organization itself, and participants were also identified as part of the talent management process. Therefore, they cannot be treated as evidence that mentoring alone caused the increase in performance.

5. Alexandria Real Estate Equities: 32% of program participants were promoted

A concrete example comes from Alexandria Real Estate Equities.

In 2023, 177 employees participated in the mentoring program, who were paired with senior leaders from across the organization. The program’s goals included, among other things, supporting knowledge transfer, building relationships and improving communication between functions and regions.

The company reported that 32% of program participants were promoted in 2023. That’s a figure that well illustrates the potential of mentoring as a tool for supporting career development.

It’s worth being precise: that doesn’t mean mentoring ‘increased the chances of promotion to 32%’. We don’t have an appropriate control group here. We can, however, say that 32% of program participants were promoted.

That’s an important distinction, especially if the organization later wants to use program data to report on its effectiveness.

What do all these mentoring programs have in common?

At first glance we have very different organizations and very different goals. One company uses mentoring to increase the productivity of new employees. Another builds a global network of relationships among employees. Yet another supports promotions for women, leadership development, or onboarding new hires.

However, one common thread runs through all these cases: mentoring is not an end in itself. Organizations implement it to address a specific business need.

This might be faster knowledge transfer. It might be talent development, increased internal mobility, preparing future leaders, or supporting new employees. In other cases, mentoring helps break down organizational silos and build relationships between people who wouldn’t otherwise have the opportunity to work together.

This leads to an important conclusion for HR and L&D: instead of asking: “Should we implement mentoring?”, it’s better to start with the question: “What organizational problem do we want to solve with mentoring?”. Then decide how the program should look.

Does mentoring reduce employee turnover?

This is one of the most tempting conclusions from many case studies, but also one of those that calls for the greatest caution.

Principal reported that program participants were about 50% less likely to leave. Sodexo also showed high retention among participants. On the other hand, a rigorous experiment described in “Management Science” did not find a significant effect of mentoring on retention.

That does not mean mentoring cannot support retention. A more accurate conclusion is: retention should not be treated as an automatic outcome of every mentoring program.

If an organization wants to influence turnover, mentoring should be part of a broader system of initiatives related to employee experience, development, career paths, and engagement.

Does mentoring increase the number of promotions?

Here too the data are promising, but they require context.

Very concrete figures appear in different organizations: 30% promotions at International SOS, 32% at Alexandria Real Estate Equities, 50% in TransDigm’s program, and 70% in the European mentoring project at Nippon Gases.

However, we cannot compare these numbers one-to-one. Programs differ in participants, duration, objectives, and recruitment methods.

Moreover, some of them are aimed specifically at high-potential individuals. It is therefore natural that their participants may be promoted faster than the organizational average.

A good measure of mentoring effectiveness should take into account not only the number of promotions, but also who participated in the program, what their goals were, and what their situation looked like before starting mentoring.

The most interesting lesson: mentoring must be designed for a specific objective

Reviewing these examples shows one more thing: there is no single universal “mentoring program”. We would design mentoring differently for new hires, differently for a program for women preparing for leadership roles, and differently again for a global program covering more than a thousand participants.

Goals, matching criteria, program length, the way mentors and mentees work, and KPIs vary. Therefore, before the organization starts recruiting participants, it should answer a few basic questions:

Why are we launching the program? Who do we want to include in mentoring? What change do we want to achieve? How will we measure the results?

Only then can you design the program structure, the matching, and the way participants will work.

How to measure the effects of a mentoring program?

Case studies also show that it’s worth looking at mentoring effectiveness more broadly than just through participant satisfaction.

Depending on the program’s goal, you can analyze, among other things, productivity, promotions, retention, internal mobility, achievement of development objectives, competence growth, or engagement levels.

It’s also worth measuring the process itself: pair activity, session frequency, completion of stages, or satisfaction with matching.

At Mentiway we have been collecting data on participants’ experiences for years. In our study covering 613 surveys from 43 mentoring programs, as many as 96.53% of respondents rated mentoring positively as a development method, and more than 95% were satisfied with their pairings.

Such data do not replace business KPIs, but they allow you to check whether the program was well designed and whether participants are actually using the process.

What does this mean for an organization planning mentoring?

The most interesting conclusion from the described case studies is not “mentoring works.” It’s far more practical:

Mentoring works best when it’s designed as a response to a specific organizational need. It can support productivity, talent development, onboarding, leadership development, diversity, or knowledge transfer. But each of these objectives requires a slightly different program and different measurement methods.

It is equally important not to view mentoring solely through the lens of the end result. A well‑designed program should have the right structure, prepared mentors, thoughtful matching, clearly defined goals and mechanisms to monitor the process. Then mentoring becomes a tool for implementing a concrete development strategy for the organization.

What does this look like in practice at Mentiway?

International case studies are a useful point of reference, but they do not replace experience from real programs run by organizations.

At Mentiway we support companies, universities and foundations in designing and running mentoring programs. On our website you will find case studies of mentoring programs implemented with Mentiway, covering different types of organizations and various development goals.

For example, we describe programs delivered for BORG Automotive, Sofixit, Women in Law and the Wrocław University of Economics. In the latter case, the platform helped, among other things, to automate recruitment, pair matching and program monitoring.

However, we cannot publish details of all the programs we run. Many organizations treat the specifics of their development processes as internal information. Therefore, if you want to learn how mentoring might look in an organization similar to yours, it’s best to talk to us directly.

Summary: mentoring can deliver measurable results, but you need to know what to look for

Case studies from various organizations show that mentoring can support very different areas of a company’s operations. The strongest methodological example demonstrates a significant increase in the productivity of new employees. Other organizations report higher promotion rates, greater retention, the development of women, or the use of mentoring as part of leadership development.

At the same time, the data show something even more important: not every positive outcome can be automatically attributed to mentoring. Therefore, a mature approach to mentoring should combine participant experience, program data and appropriately selected business KPIs. Only then can you answer not just the question:

“Do participants like mentoring?”, but above all: “Is the program achieving the goal for which it was launched?”

That’s the difference between mentoring as an interesting HR initiative and mentoring as a deliberately designed tool for organizational development.

FAQ: Mentoring in companies and case studies

Does mentoring really work?

Yes, both experimental studies and data from company programs show positive effects of mentoring. The most robust experiment described here found roughly a 19% increase in sales revenue among mentored new hires.

What outcomes of mentoring can be measured?

Depending on the program’s goal, you can measure productivity, promotions, retention, internal mobility, competency development, goal attainment, engagement, and participant satisfaction.

Does mentoring increase employee retention?

It can support retention, but it shouldn’t be treated as a guaranteed effect. Some companies report lower turnover among participants, but an experimental study from 2025 found no effect of mentoring on retention.

Does mentoring help with promotions?

Many organizations report high promotion rates among participants in mentoring programs. However, it’s important to check whether the program had a comparison group and who was recruited into it.

Can mentoring be used during onboarding?

Yes. ATEN is an example of an organization that combined mentoring for new employees with a 30/60/90-day onboarding plan.

Can mentoring be part of a talent development program?

Absolutely. Examples from pladis, TransDigm and HEINEKEN show that mentoring can be combined with talent management and leadership development.

Does Mentiway run mentoring programs for companies?

Yes. Mentiway supports organizations in designing and running mentoring programs, including recruitment, matching, participant engagement, program monitoring and measuring outcomes. See Mentiway case studies or check Mentiway’s report on participants’ experience of mentoring.

Would you like to create a mentoring program in your organization?

If you’re wondering how to design a program tailored to your organization’s goals, we will help you translate best practices from similar implementations into a concrete process.

Talk to us about a mentoring program for your organization!