The CEO's Guide to Corporate Finance outlines four principles, or cornerstones, to help executives make strong financial decisions independently of the CFO. The four cornerstones are: 1) the core-of-value principle focuses on returns on capital and growth as drivers of value, 2) the conservation-of-value principle states that only improving cash flows creates value, 3) the expectations treadmill principle explains how share prices reflect changing expectations rather than just performance, and 4) the best-owner principle states that a business's value depends on its owner and strategy. Applying these principles can help executives evaluate acquisitions, divestitures, projects, and compensation to make decisions that create rather than destroy value.