Agile is something that I’ve previously found to work very well with in-house R&D projects, and rather more challenging when negotiating projects with customers.
The challenge is getting from the sales cycle through to the agile development iterations, be they sprints or otherwise.
By using an agile process, the advantage is that many smart people have been here before. Some of the knowledge is locked up in consultancy houses, while some of it is shared.
Gerard Meszaros has a good presentation highlighting some of the challenges and what often gets missed. The slides are available here.
The section on adding more time into the Product Planning phase fits well with how customers often see projects. By providing scope at the feature level, it allows boundaries to be placed around time and money.
This is certainly an area of agile that I would like to understand more.