  Interferometric experiments of the reionization era offer the advantages of
measuring power in spatial modes with increased sensitivity afforded by
multiple independent sky measurements. Here we review early work to measure
this signal, current experiments, and future opportunities, highlighting the
lessons learned along the way that have shaped the research field and
experimental design. In particular, this chapter discusses the history,
progress, challenges and forecasts for detection and exploration of the spatial
structure of the 21~cm brightness temperature signal in the Epoch of
Reionisation using interferometric experiments. We discuss GMRT, PAPER, LOFAR,
MWA, and the future HERA and SKA.
