For a Centers Cross Run, each center dancer will be running past the midpoint of the line, to become the new end dancer in the other half of the line. The original end dancers will be sliding inward one position to become the new center dancers.
For an Ends Cross Run, each end dancer will be running to the center position in the other half of the line. The center dancers will be sliding outward one position, to become the new end dancers.
As with Run, the dancers who were named are turning around halfway (180 degrees) as they do the action, while the others don't turn at all.
For a Centers Cross Run when the center dancers are facing the same direction, they must get past each other on their way to the other half of their line. The dancer on the right goes in front of the dancer on the left, as if they were starting to do a Half Sashay.