  We classify gradings by arbitrary abelian groups on the classical simple Lie
and Jordan superalgebras $Q(n)$, $n \geq 2$, over an algebraically closed field
of characteristic different from $2$ (and not dividing $n+1$ in the Lie case):
fine gradings up to equivalence and $G$-gradings, for a fixed group $G$, up to
isomorphism.
