My 1:1 marketing startup DirecTouch began sprinting in 1994. I didn't know anything about software development, and so I focused on finding a good way to collaborate with engineers. I picked Ivar Jacobson's iterative & incremental Objectory which became the Unified Process, than RUP, then IBM RUP. I had to close the startup, but I learned a lot about product development and solution delivery.
In the summer of 2000, I started coaching. I've worked with large companies on long engagements ever since, learning a lot and actively contributing to the evolution of Agile: Scrum, Essential Unified Process, Scaled Agile Framework (SAFe), Kanban, TameFlow, Theory of Constraints, and XSCALE!