What is Strategy

The dominant idea in the field of strategy - that success consists of establishing a unique competitive position, sustained for long periods of time - is no longer relevant for most businesses. In the 1960s, Peter Drucker told us that strategy was how we competed on price. In the 1980s, Michael Porter redefined it around his Five Forces and recently it is being redefined by Gail McGrath and Clayton Christsenson by change.

How do you define Strategy?