  We investigate the concept of dominion (in the sense of Isbell) in several
varieties of nilpotent groups. We obtain a full description of dominions in the
variety of nilpotent groups of class at most two. Then we look at the behavior
of dominions of subgroups of groups in ${\cal N}_2$ when taken in the context
of ${\cal N}_c$ with $c>2$. Finally we establish the existence of nontrivial
dominions in the category of all nilpotent groups.
