Sleep Again vs. Why We Sleep: Which Book Should You Read?

I've been asked this question a few times since people learned I was writing a sleep book. Matthew Walker's Why We Sleep is one of the most popular science books of the past decade. It sold millions of copies and shifted how people think about rest.

So why write another sleep book? The short answer: because they're different books for different problems. Walker's book explains why sleep matters. Mine explains how to fix it when your entrepreneurial brain won't let you.

Here's an honest breakdown of both.

Different Authors, Different Perspectives

Why We Sleep is written by Matthew Walker, a neuroscience and psychology professor at UC Berkeley who has spent his career researching sleep in a lab. He brings decades of academic rigor and a deep understanding of how sleep works at the neurological level.

Sleep Again is written by me, an entrepreneur who has been founding companies for 20 years and investing in startups for 6 years. I'm not a sleep scientist. I'm a founder who spent years battling insomnia, researching the science, and testing strategies on himself. The book includes 87 endnotes referencing peer-reviewed studies, but the lens is always practical.

Walker approaches sleep as a researcher. I approach it as someone who needed to fix a problem while running a company.

Different Audiences

Why We Sleep is written for a general audience. It covers sleep's role in health, disease, memory, creativity, and public policy. It makes the case that sleep deprivation is a public health crisis. Anyone can benefit from reading it, whether you're a student, a parent, or a CEO.

Sleep Again is written specifically for entrepreneurs, startup founders, and people in high-pressure roles. It addresses challenges that general sleep books don't touch: fundraising stress, decision fatigue, the guilt of resting when there's work to do, overtraining from pushing too hard at the gym, and the 3am wake-up when your mind cycles through business scenarios all night.

What Each Book Does Best

Why We Sleep is unmatched in making the scientific case for sleep. Walker's explanation of how sleep deprivation affects the prefrontal cortex, the brain region responsible for impulse control and complex reasoning, is particularly relevant for founders. His data on the relationship between sleep and Alzheimer's disease is sobering. If you need motivation to prioritize sleep, this book delivers it.

Sleep Again is built around practical strategies. The Mental Bouncer Technique for falling back asleep at 3am. How to restructure your workouts so they stop wrecking your sleep. The specific protocol for when caffeine helps versus when it hurts. How to recognize whether your early-morning insomnia is caused by stress, overtraining, or both. It includes interviews with a dozen founders about their worst sleep periods and what helped them recover.

Head-to-Head Comparison

Category	Why We Sleep	Sleep Again
Author	Neuroscience professor	20-year entrepreneur
Audience	General public	Entrepreneurs & founders
Primary focus	Why sleep matters	How to fix your sleep
Tone	Academic, alarming	First-person, practical
Science depth	Deep neuroscience	Applied science (87 endnotes)
Practical strategies	Limited	Core of the book
Founder-specific content	None	Fundraising stress, overtraining, decision fatigue, chronotype scheduling
Real-world interviews	Clinical case studies	Dozen+ founder interviews
Length	~100,000 words	~54,000 words (27 chapters)

What Why We Sleep Doesn't Cover

Walker's book doesn't address the specific stressors that keep entrepreneurs awake. It doesn't cover how fundraising creates a cortisol loop that disrupts sleep for months. It doesn't discuss how overtraining at the gym can cause 4am wake-ups. It doesn't offer mental techniques for when your brain starts running through tomorrow's investor meeting at 3am.

That's not a criticism. It wasn't designed to. It was designed to present the science, and it does that brilliantly.

What Sleep Again Doesn't Cover

My book doesn't go as deep into the neuroscience of sleep stages, the evolutionary history of sleep across species, or the public policy implications of sleep deprivation in society. It references Walker's research in several places, but it doesn't attempt to replace the scientific depth of his work.

If you want to understand what happens in your brain during REM sleep at a cellular level, Walker's book is better. If you want to know why you keep waking up at 4am and what to do about it as a founder, mine is.

My Recommendation

Read both. They complement each other.

Start with Sleep Again if you're a founder dealing with sleep problems right now. The strategies are immediately applicable and designed for your specific situation. Then read Why We Sleep for the deeper scientific understanding that reinforces why those strategies matter.

Start with Why We Sleep if you're not sure whether sleep is really the problem. Walker's book will convince you it is. Then pick up Sleep Again for the tools to fix it.

They're not competing books. They're different parts of the same puzzle. One explains the problem. The other provides the solution, specifically for the kind of person who builds companies.