New insights fail to get put into practice because they conflict with deeply held internal images of how the world works...images that limit us to familiar ways of thinking and acting. That is why the discipline of managing mental models - surfacing, testing, and improving our internal pictures of how the world works - promises to be a major breakthrough for learning organizations.

Teams, not individuals, are the fundamental learning unit in modern organizations. This is where the "rubber stamp meets the road"; unless teams can learn, the organization cannot learn.

The company-as-a-machine model fits how people think about and operate conventional companies. And, of course, it fits how people think about changing conventional companies: You have a broken company, and you need to change it, to fix it.

Learning organizations organizations where people continually expand their capacity to create the results they truly desire, where new and expansive patterns of thinking are nurtured, where collective aspiration is set free, and where people are continually learning how to learn together.

Consider prejudice. Once a person begins to accept a stereotype of a particular group, that "thought" becomes an active agent, "participating" in shaping how he or she interacts with another person who falls in that stereotyped class. In turn, the tone of their interaction influences the other person's behaviour. The prejudiced person can't see how his prejudice shapes what he "sees" and how he acts. In some sense, if he did, he would no longer be prejudiced. To operate, the "thought" of prejudice must remain hidden to its holder

When you ask people what it is like being part of a great team, what is most striking is the meaningfulness of the experience. People talk about being part of something larger than themselves, of being connected, of being generative. It becomes quite clear that, for many, their experiences as part of truly great teams stand out as singular periods of life lived to the fullest.

Learning to see the structures within which we operate begins a process of freeing ourselves from previously unseen forces and ultimately mastering the ability to work with them and change them.