String theory on AdS3 x M7 in the tensionless limit

We review old and recent results on a special limit of string theory on AdS(3) x M-7 with pure NS-NS fluxes: the limit in which the string length l(s) = root alpha' equals the AdS(3) radius R. At this point of the moduli space, the theory exhibits special properties, which we discuss. Special attention is focused on features of correlation functions that are related to the noncompactness of the boundary CFT target space, and on how these features change when the point k (math) R-2/alpha' = 1 is approached. Also, we briefly review the recent proposals for exact realizations of AdS/CFT correspondence at this special point.