  Star complexes are the highest level groupings in the hierarchy of the
embedded young stars, clusters and associations, which obey the size - age
relation. Starburst clumps, superassociations, supergiant HII regions are
different titles for the groupings of the same size as complexes but with
active star formation over all the grouping. The coherent star formation in the
regions of violent star formation was probably triggered by external pressure.
The issue of gravitational boundness of complexes and superassociations is
briefly discussed
