Don’t be fooled into thinking that you don’t need to do any design when you adopt Agile. Agile development strives to deliver business value early and often, focusing on getting working software to market as soon as possible rather than dwelling in documentation and ‘analysis paralysis’. But let’s be clear, “business value” and “working software” are not the same thing. You can quite easily get something into production that fails to generate revenue, decrease costs or whatever other yardstick you use for ‘value’. What differentiates the two of them is design. I don’t mean big up front design that details all the features and provides a concrete spec, I mean a design vision that articulates what the product goals are and a roadmap for getting there. And what is a design vision? A short statement of intent is a good place to start, and soon after a user interface mocked up in pen and ink. It is cheap and easy and helps bridge the path from idea to execution.