  We examine the integrated Sachs-Wolfe (ISW) imprint of voids and
superclusters on the cosmic microwave background. We first study results from
the Jubilee $N$-body simulation. From Jubilee, we obtain the full-sky ISW
signal from structures out to redshift $z=1.4$ and a mock luminous red galaxy
(LRG) catalogue. We confirm that the expected signal in the concordance \Lambda
CDM model is very small and likely to always be much smaller than the
anisotropies arising at the last scattering surface. Any current detections of
such an imprint must, therefore, predominantly arise from something other than
an ISW effect in a \Lambda CDM universe. Using the simulation as a guide, we
then look for the signal using a catalogue of voids and superclusters from the
Sloan Digital Sky Survey. We find a result that is consistent with the \Lambda
CDM model, i.e. a signal consistent with zero.
