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Twenty? As many as there are companies?
At the highest level of competitive differentiation there are 3 (but it is still hard to get it right).
Technology changes...strategy doesn't. Change happens faster....strategy doesn't.
THE WORLD'S MOST FAMOUS BUSINESS-SCHOOL PROFESSOR IS FED UP WITH CEOS WHO CLAIM THAT THE WORLD CHANGES TOO FAST FOR THEIR COMPANIES TO HAVE A LONG-TERM STRATEGY. IF YOU WANT TO MAKE A DIFFERENCE AS A LEADER, YOU'VE GOT TO MAKE TIME FOR STRATEGY.
http://www.fastcompany.com/42485/michael-porters-big-ideas
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