Abstract: LEGO has built a global empire and become a household name, thanks to the interlocking bricks that its founders developed half a century ago. But the company almost went belly up in the early 2000s due to a binge of innovation that took it too far away from what LEGO did best. In a new book, Wharton practice professor David Robertson details how thinking too far "outside the box" almost bankrupted LEGO -- and how the company found a winning formula by turning to innovation "inside the brick."