The Seven Principles of Lean Software Development

#1 Eliminate Waste

• Remove all non-value adding waste
• Myth: Early specification reduces waste
  

#2 Build Quality In

• Use inspection to prevent defects, not recognize them afterwards
• Myth: The job of testing is to find defects

#3 Create Knowledge

• Use feedback every step of the way; only then can complexity be tamed -- it's never available beforehand
• Myth: Predictions create predictability

#4 Defer Commitment

• Schedule irreversible decisions to occur at the last possible moment
• Myth: Planning is commitment

#5 Deliver Fast

• Minimize time from concept to cash by maximizing throughput
• Myth: Haste makes waste

#6 Respect People

• Use responsibility based planning and control; reward sphere of impact, not span of control
• Myth: There is one best way

#7 Optimize the Whole

• A lean organization optimizes the entire value stream; any other optimization is sub-optimal for the overall organization
• Myth: Optimize by decomposition

From: Implementing Lean Software Development by Mary and Tom Poppendieck, Addison- Wesley, 2007