Ordinarily, when you resize a picture box, the box changes size but the picture doesn't. Similarly, if you resize a text box, the box will change size and the text inside it will simply reflow to fit the new size and shape of the box. This tutorial shows a simply technique for resizing the contents of the box as well as the box itself.
Picture boxes
To import a picture in QuarkXPress, highlight the appropriate picture box and choose File > Get Picture.
A simply way of making the picture box exactly the right size for the picture you have just imported is to choose Style > Fit Box to Picture. The box will expand or contract to match the size of the picture precisely, but how do you then resize the box while maintaining this match?
As you will see from the following movie, if you resize the box, the size of the picture does not change and the box no longer matches the picture.