  We study half-BPS surface operators in four dimensional N=2 SU(N) gauge
theories, and analyze their low-energy effective action on the four dimensional
Coulomb branch using equivariant localization. We also study surface operators
as coupled 2d/4d quiver gauge theories with an SU(N) flavour symmetry. In this
description, the same surface operator can be described by different quivers
that are related to each other by two dimensional Seiberg duality. We argue
that these dual quivers correspond, on the localization side, to distinct
integration contours that can be determined by the Fayet-Iliopoulos parameters
of the two dimensional gauge nodes. We verify the proposal by mapping the
solutions of the twisted chiral ring equations of the 2d/4d quivers onto
individual residues of the localization integrand.
