Adam Hayes, Ph.D., CFA, is a financial writer with 15+ years Wall Street experience as a derivatives trader. Besides his extensive derivative trading expertise, Adam is an expert in economics and ...

Twenty years after the introduction of the theory, we revisit what it does—and doesn’t—explain. by Clayton M. Christensen, Michael E. Raynor and Rory McDonald Please enjoy this HBR Classic. Clayton M.

Sixty years ago, Rosa Parks refused to give up her seat on a bus in Montgomery, Ala. Her courageous act is now American legend. She is a staple of elementary school curricula and was the second-most ...