The article “Familiar Metric Management – Small is Beautiful Once Again” (PDF) by Lawrence H. Putnam and Ware Myers discusses the fact that in software development projects, small teams are more efficient than larger one. They provides metrics showing that the concept of using small teams in software development is a really beautiful idea. The data was provided by 491 medium-sized projects between 35,000 and 95,000 working on new or modified source lines of code. This data shows that productivity of small project teams is higher and suggests that you should develop software in teams of three to seven. If you use teams larger than seven, you will pay a severe penalty in the time and effort a project takes.