  Consider the problem \begin{eqnarray*} -\Delta u &=& v^{\frac 2{N-2}},\quad
v>0\quad {in}\quad \Omega, -\Delta v &=& u^{p},\:\:\:\quad u>0\quad {in}\quad
\Omega, u&=&v\:\:=\:\:0 \quad {on}\quad \partial \Omega, \end{eqnarray*} where
$\Omega$ is a bounded convex domain in $\R^N,$ $N>2,$ with smooth boundary
$\partial \Omega.$ We study the asymptotic behaviour of the least energy
solutions of this system as $p\to \infty.$ We show that the solution remain
bounded for $p$ large and have one or two peaks away form the boundary. When
one peak occurs we characterize its location.
