I'm in this business because I find it interesting and challenging. As a consultant or as a programmer, I like to be involved early on in a project; I think most projects succeed or fail early on, during the requirements and technical design stages, and so I like to be involved there. But I can pick up the ball and run with it at any stage, bringing a customer-focussed, pragmatic approach while keeping true to the fundamental engineering principles which must underlie any successful system.
Primarily, I design and build software systems. But to me, a good engineer isn't hidden in the back corner of the basement office, coding to the green glow of a monochrome monitor.