Eleanor Dillon, Sonia Jaffe and Nicole Immorlica of Microsoft Research and Christopher Stanton of Harvard Business School ran a six-month field experiment with 7,137 knowledge workers at 66 companies. Half of them, chosen at random, got an AI assistant built into the email, document and meeting apps they already used. In the second half of the experiment, the regular users spent about two hours less on email each week and did less work outside regular hours. Time in meetings barely moved, and the mix of tasks stayed the same.¹
The pattern makes sense. Email is something each of us can change alone. A meeting belongs to everyone in the room: shortening it takes an agreement, and one person with a new tool seldom starts that conversation. The authors conclude that giving individuals AI mainly changes what people can change on their own. Three of the four authors worked for Microsoft, which makes the tool, and the paper is a working paper that has yet to go through peer review.
Talent Takeaway
The first gains from AI often arrive on their own, one inbox at a time. The larger ones sit in how a team works together: which meetings we still need, who drafts what, how work gets handed over. That is a conversation for the whole team, and a good one to start once the tool is in place. Maybe a question for our next team meeting: what would we do differently if everyone here had an assistant?
¹ Dillon, E. W., Jaffe, S., Immorlica, N., & Stanton, C. T. (2025). Shifting work patterns with generative AI (NBER Working Paper No. 33795). National Bureau of Economic Research. https://www.nber.org/papers/w33795
Further reading: AI Made Consultants 40% Better, With One Catch
