  We determine the primitive ideal space and hence the ideal lattice of a large
class of separable groupoid C*-algebras that includes all 2-graph C*-algebras.
A key ingredient is the notion of harmonious families of bisections in etale
groupoids associated to finite families of commuting local homeomorphisms. Our
results unify and recover all known results on ideal structure for crossed
products of commutative C*-algebras by free abelian groups, for graph
C*-algebras, and for Katsura's topological graph C*-algebras.
