I picked up Playful expecting a fun read. I got something more: validation.For years I've run my business like a sandbox — testing ideas, encouraging my teams to take big swings and fail big, treating challenges as puzzles rather than problems. That approach has always felt a little countercultural in rooms where "serious" is the highest compliment. Cas Holman's book is the first time I've seen that way of working articulated so clearly, and backed up by so much thinking about why it actually works.Holman — a toy designer, former RISD professor, and one of the featured thinkers in Netflix's Abstract — makes the case that free play (unstructured, self-directed, internally motivated) isn't just for kids. It's the foundation for creativity, adaptability, and the kind of wellbeing that productivity culture has trained most of us out of. She draws on her own experience designing for places like the High Line, weaves in the research, and tells stories that stick.What I loved most is how playfully the book itself is written. I underlined constantly and left exclamation points in the margins. It doesn't lecture. It invites.If you're mired in responsibility, if adulthood has started to feel like a narrow corridor, or if life is just feeling hard — this is your resource. Holman reminds you that play isn't a reward for finishing your to-do list. It's how you meet the list in the first place.