The call Flip the Diamond turns a diamond into a wave -- or some other kind of line, depending on how the dancers in the diamond were originally facing.

The centers of the diamond do a Diamond Circulate, moving to the point spots, and become the ends of the new wave or line.

At the same time, the points of the diamond "flip" inward, into the empty space, becoming the centers of the new wave or line.

The centers turn around halfway (180 degrees) as they move into the center, just like on a Run or Trade. Their action is the same as if they were running around, or trading with, an imaginary dancer standing in the spot where they had been "pointing".