The Bogleheads' Guide to Investing

This is what passes for a textbook in the index-fund world, and it's a better textbook than 90% of what business schools assign. Larimore, Lindauer, and LeBoeuf are evangelists for Jack Bogle's gospel — that costs and behavior matter more than stock picking — and they make the case so methodically that it's hard to walk away unconvinced. Where Collins's Simple Path is a deliberately narrow program, Bogleheads is the encyclopedia. Need to understand bond duration? In here. Need to decide between Roth and traditional? In here. Need to model your withdrawal strategy in retirement? In here. The treatment of taxes alone — what to hold in which account, when to harvest losses, how to minimize lifetime tax — can save readers far more in friction costs than the price of the book. It's a book worth keeping on the shelf and re-opening as life changes. Pair with The Simple Path to Wealth for the same philosophy in two complementary depths. Five worms. The reference manual every index-fund investor needs.