Observations of the redshifted 21-cm line promise to be the best probe 
of the evolution of the intergalactic medium (IGM) prior and during 
reionization, allowing the study of the first luminous structures, 
their evolution and their interplay with the IGM. I will present our 
most recent upper limits on the 21-cm emission in the 7 < z < 23 range 
and how they constrain the thermal history of the IGM. I will conclude 
by presenting what we will be able to achieve with the Hydrogen Epoch of 
Reionization Array (under construction) and the (future) Square Kilometre Array.