The 70-20-10 model holds that people learn roughly 70 percent from challenging experiences on the job, 20 percent from other people and 10 percent from formal training.
Where it comes from
The idea grew out of research at the Center for Creative Leadership. Morgan McCall, Michael Lombardo and Ann Morrison asked successful executives about the key events that had shaped them and published the results in The Lessons of Experience in 1988.¹ The tidy ratio appeared later, in a development planning guide by Lombardo and Robert Eichinger.²
Where it goes wrong
The numbers are often presented as a measured law of learning, and occasionally used to cut training budgets. They rest on executives' recollections, and a 2018 review found little empirical support for the specific split.³ Many practitioners read the model as a reminder that experience, relationships and training work together.
Talent Takeaway
For each person's next development step, plan all three: a stretch assignment, someone to learn from, and a course or book that gives them a framework. The connection between the three matters more than the proportions.
¹ McCall, M. W., Jr., Lombardo, M. M., & Morrison, A. M. (1988). The lessons of experience: How successful executives develop on the job. Lexington Books.
² Lombardo, M. M., & Eichinger, R. W. (1996). The career architect development planner. Lominger.
³ Clardy, A. (2018). 70-20-10 and the dominance of informal learning: A fact in search of evidence. Human Resource Development Review, 17(2), 153–178.
Further reading: McCauley, C. D., DeRue, D. S., Yost, P. R., & Taylor, S. (Eds.). (2013). Experience-driven leader development. Wiley.