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the exchange about the wrench as written and have audiences rolling in the aisles because of the familiar interactions of their characters, but during an improv, such bickering only delays the furtherance of action.
    In the hands of a writer, a disagreement can reveal hidden aspects of characters, aim the scene in a new direction, or convey other valuable information. When two improvisers are on stage arguing, they are only preventing something more interesting from happening.
    Fortunately, there is a very simple way for even a first- time player to promote agreement.
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Yes &
    "Yes, & . . ." is the most important rule in improvisation (the corporate name for the ImprovOlympic is "Yes & . . . Productions"). By following this simple rule, two players can build a scene before they know it.
    The "Yes, & ..." rule simply means that whenever two actors are on stage, they agree with each other to the Nth degree. If one asks the other a question, the other must respond positively, and then provide additional information, no matter how small: "Yes, you're right, and I also think we should . .." Answering "No" leads nowhere in a scene:
    A: Do you want to go to the movies?
    B: No.
    Even a positive answer is insufficient:
    A: Do you want to go to the movies?
    B: Yes
    The "Yes, & ..." rule will lead players to their scene:
    A: Do you want to go to the movies?
    B: Yes, and let's go off our diets and eat a lot of greasy popcorn.
    OR
    B: Yes, let's sneak out of the house through the basement.
    OR
    B: Yes — is anybody picketing anything? I feel like counter-protesting.
    With "Yes, & . .." there are an unlimited number of scenic possibilities, and each player continues to supply information.
    In this way, one step at a time, each player provides a building block, until they have easily, painlessly, constructed a scene. Answering "Yes, but..." stops any continued growth, while a flat "No" erases the block that has just been established.
    Construction metaphors aside, this is a very relaxing way in which to work. A player knows that anything he says on stage will be immediately accepted by his fellow player, and treated as if it were the most scintillating idea ever offered to mankind. His partner then adds on to his idea, and moment by moment, the two of them have created a scene that neither of them had planned.
    Agreement is the one rule that can never be broken: players must be in agreement to forward the action of the scene.
    When improvisers meet on stage, they agree to accept each other's initiations; they must completely commit to the reality they create^ for each other without a moment's hesitation. No matter how much of an improv cliché the line has become, if the first player says, "Well, here we are in Spain," then everyone on stage accepts that they are indeed in Spain. The next player might say, "Look out for that bull," and everyone is in the path of a charging bull. And so the scene is built.
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Each new initiation furthers the last one, and the scene progresses. The acceptance of each other's ideas brings the players together, and engenders a "group mind." Denying the reality that is created on stage ends the progression of the scene, and destroys any chance of achieving a group consciousness.
    Denials are taboo in improvisation. Being a good team player means having ethics. One of the best examples of denial in improv occurred during the early days of Second City, when Del and Joan Rivers were in the same company, and it rankles him to this day.
    One night during an improvised scene, Joan told Del that she wanted a divorce. Del responded as an emotionally distraught husband might, in the hope of getting her to reconsider. "But honey, what about the children?" She replied, "We don't have any children!"
    Naturally, she got a huge laugh. Naturally, she had completely destroyed the scene.
    Rivers' laugh was at the expense of the scene, and she lost the trust of a fellow player. Her reply was a blatant denial of Del's