The discovery of integrability in the large N limit of the prototypical realization of the AdS/CFT correspondence has raised the hope that the spectrum of scale dimensions in N=4 SYM (and strings in AdS_5 x S^5) might be known exactly, i.e. to all orders in the coupling constant. So far, most of the efforts focused on closed strings and periodic boundary conditions. In this talk I will discuss how these ideas are extended to open string and open boundary conditions. In particular how to obtain exact expressions for the boundary scattering matrices, discuss the integrability of the boundary conditions and how finite size effects may be taken into account.