A few powerful practices and processes support lean and agile
Prince2 knows 7 principles, 7 processes and 7 themes.
CMMi for product development describes 22 Process Areas and 13 generic goals and practices.
COBIT recognizes 318 management goals
Most of them make good sense. The frameworks are well thought out. They even allow customization to your specific situation.
In contrast, agile tools are much less complex.
Extreme programming recognizes 13 practices, Scrum has 5 values and 6 meetings, Kanban has 4 principles.
It reminds us of the urban legend that NASA spent millions of dollars on developing a ballpoint pen for use in space. The Russians just used pencils. Not true, but you get the idea.
The simpler methods and principles do not just do the job. Their simplicity actually makes them more powerful. They are easier for everybody to understand and follow. As a consequence, they can be applied by the teams and people themselves, without management and strict supervision. They are not management tools for manager, they are tools for self-management by teams.
XP eXtreme Programming
eXtreme Programming is a cornerstone in agile software development. The XP practices of test driven development and continuous integration enable the small releases that have revolutionized the software industry.
Although the word extreme does not suggest it, XP has its main focus on quality: test driven development, simple design, coding standards, refactoring, pair programming all contribute to quality, collective ownership diminishes the risks if a developer has to leave the team.
Some XP practices overlap with Scrum (planning game, customer tests) and Kanban (sustinainable pace, small releases). All approaches go well together.
XP has been the main source of inspiration for both the SAFe® framework (Scaled Agile) and of Devops.