  This thesis aims to make precise the microscopic understanding of Hawking
radiation from the D1/D5 black hole. We present an explict construction of all
the shortmultiplets of the ${\cal N}=(4,4)$ SCFT on the symmetric product
$\tilde{T}^4/S(Q_1Q_5)$. An investigation of the symmerties of this SCFT
enables us to make a one-to-one correspondence beween the supergravity moduli
and the marginal opeerators of the SCFT. We analyse the gauge theory dynamics
of the splitting of the D1/D5 system into subsystems and show that it agrees
with supergravity. We have shown that the fixed scalars of the D1/D5 system
couple only to (2,2) operators thus removing earlier discrepancies between
D-brane calculations and semiclassical calculations. The absorption
cross-section of the minimal scalars is determined from first principles upto a
propotionality constant. We show that the absorption cross-section of the
minimal scalars computed in supergravity and the SCFT is independent of the
moduli.
