When a set of screen elements are identified as a family a bounded extent is placed around the identified elements. Items can be automatically grouped based on their association with a set of data defined in a DBMS as a family, for example. When one of the elements within the group is moved, the extent automatically resizes to a new geometry that fits around each of the elements within the group. If an element within the group is moved against the extent and then extended beyond the boundaries of the extent, the extent automatically resizes to cover a bigger area; if an element within the group that is against the extent is moved inside the boundary of the extent, the extent automatically resizes to cover a smaller area. It is possible to nest a set of these extensible groups within a single extensible group thereby providing maximum flexibility while still maintaining optimal flexibility. In addition, it is possible to “unlink” an item so that it maintains its association with the group but does not effect the extent.