You probably don’t need to have much of an imagination to envision just how intimidating it can be to be a first-time CEO within your first 90 days. I remember my own such experience like it was yesterday, and still remember it as a time in my life where I was, paradoxically, both excited and insecure, confident and fearful, relieved and anxious, tired and energized. How to approach the first 90 days as a new CEO, including what to do and what not to do, is also among the most frequently asked questions that I’ve received over the past 14 years. For this reason, I thought it would be helpful to interview 3 CEOs, each at different stages of their respective leadership journeys, to ask each of them the same 3 questions: (1) Their general approach to the first 90 days (2) What worked (and what they'd be sure to do again) (3) What didn’t work (and what they'd definitely *not* do again) I think you’ll find their answers to be highly instructive, particularly the themes that seemed to be consistent across all 3 of their stories. Thank you to my guests: John O'Brien, CEO of Echo Point Books & Media, Matt Fiedelholtz, co-CEO of Stage 2 Data, and Ethan Walz, co-CEO of Allied Electric. redacted