  In this article we study giant gravitons in the framework of AdS/CFT
correspondence. First, we show how to describe these configurations in the CFT
side using a matrix model. In this picture, giant gravitons are realized as
single excitations high above a Fermi sea, or as deep holes into it. Then, we
give a prescription to define quasi-classical states and we recover the known
classical solution associated to the CFT dual of a giant graviton that grows in
AdS. Second, we use the AdS/CFT dictionary to obtain the supergravity boundary
stress tensor of a general state and to holographically reconstruct the bulk
metric, obtaining the back reaction of space-time. We find that the space-time
response to all the supersymmetric giant graviton states is of the same form,
producing the singular BPS limit of the three charge Reissner-Nordstr\"om-AdS
black holes. While computing the boundary stress tensor, we comment on the
finite counterterm recently introduced by Liu and Sabra, and connect it to a
scheme-dependent conformal anomaly.
