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.

A semicolon (;) joins two complete sentences that are closely linked in meaning. They can be used instead of a full stop between related sentences, or instead of a conjunction like 'and' or 'but'. I ...