The Manifesto for Agile Software Development

We are uncovering better ways of developing software by doing it and helping others do it.
Through this work we have come to value:

    Individuals and interactions over processes and tools
    Working software over comprehensive documentation
    Customer collaboration over contract negotiation
    Responding to change over following a plan

 

http://www.agilealliance.org/the-alliance/the-agile-manifesto/