We don't do deadlines. We do scope. We estimate scope using story points and estimate the number of cycles assuming "x" story points are hit in a cycle. With clients, we share this process, giving transparency into our progress. We never promise a specific release date, and if we see the timeline stretching further than the client would like, we adjust the scope of the project to shorten the length of the project.

I've never had a better relationship with clients with another model. They get to understand more of what a real development project is. We even invite them to our Cycle Demos for their project.

The best way to not get behind is to not set a deadline. Instead set a scope and budget. Communication is key. More often than not, adding developers does not speed up a project, only adjusting scope does.

Adjust Early. Adjust Accordingly. Adjust Often.