Thirteen books on product, agile and delivery that the publisher or the author gives away in full.
Every book on this list is given away by whoever holds the right to give it away, meaning the publisher's own site, the author's own site, or a licence that permits redistribution. Nothing here is a scanned upload, a sample chapter or a promotion that has since ended, and nothing is free only through a library or a subscription. The order runs from the books most likely to change how you work in the next month down to the references you will keep open in a tab. Two of them ask you to fill in a form before the download, and the note on each of those says so.
The strongest evidence on this list that a free book can be a first rank one. Basecamp put the whole thing online and added a PDF, so there is no reason to read someone's summary of it instead.
Free because Schwaber and Sutherland decided the definition of Scrum should belong to everybody. Thirteen pages, and it settles most of the arguments that people have about Scrum without having read it.
The other framework definition worth keeping open in a tab, published under a Creative Commons licence so you can quote it and build your own training on it. Fifteen minutes to read, covering what most Kanban courses spend a day on.
Google gave away the book that named the discipline, and every conversation about error budgets and service level objectives traces back to it. Worth the download for the chapters on objectives and on blameless postmortems even if you never go near production.
The free book that explains where Shape Up came from, and still the clearest short case for cutting scope rather than moving the date. Read it straight after Shape Up for the twenty years of argument sitting behind it.
The best free answer to what Scrum actually looks like on a Tuesday, given away by InfoQ with Kniberg's blessing. Pair it with the Scrum Guide, which gives you the rules but not the experience of living with them.
The Kanban Method from the person who defined it, condensed to something you can finish in an evening and released free by its own publisher. Go here when the Kanban Guide has left you wanting the practices and cadences spelled out.
Free from InfoQ and still the fastest way to stop treating Scrum and Kanban as rival camps. Useful when somebody in your organisation is about to pick one on the strength of a conference talk.
Abby Covert put all one hundred and sixty pages on her own site, one page at a time, which is unusual generosity for a book this well regarded. It earns a place here because untangling a mess of language and structure is most of the work before anything gets built.
IDEO.org gives away fifty seven research and ideation methods, each written as something you could run this week. The most immediately practical free thing on this list if you have discovery to do and no method to hand.
Brad Frost publishes every chapter on his own site, which makes it the free reference to send someone before a design system argument rather than after one. Read it for the shared vocabulary rather than for the front end detail.
Released under a Creative Commons licence, so a book about engineering at a scale most people will never see costs nothing to consult. The chapters on deprecation and on large scale change are the ones that repay a delivery lead.
The follow up that Google also gave away, and the one to read second because it is where the worked examples live. Included for the service level objective arithmetic, which is hard to find spelled out this clearly anywhere else for nothing.