Agile Project Management
It's based on the Manifesto for Agile Software Development, created in 2001. It’s focused on collaborative workflows determined by customer’s needs, they are self-organized and constantly improving. Its flexibility comes from frequent adjustment in planing, implementation, and early deliveries and evaluations.
Due to its collaborative nature, it encourages the accountability and participation from all members of the team, including the customer, who can participate actively in the process.