The Sheffield Software Engineering Observatory has been carrying out empirical research into agile development for a number of years.

Some papers from this research include:

1.The Impact of an Agile Methodology on the Well Being of Development Teams. Empirical Software Engineering, 11(1), 143-167.

2.A Formal Experiment Comparing Extreme Programming with Traditional Software Construction. In the Proceedings of the Fourth Mexican International Conference on Computer Science (ENC 2003). Tlaxcala, Mexico, 73-80. Sep. 8-12, 2003.

3.20 Years of Teaching and 7 Years of Research: Research When You Teach, SEEFM 07.

4.A Design Change Metric Derived From Extreme X-Machines, SEEFM 07

Other papers can be found on the Observatory site.