Massive galaxies have grown a factor of 4 in size since z=2 to the present. The reasons of this growth remain unclear. Within the possible mechanisms that have been suggested to explain this evolution, the accretion of satellites by the massive galaxies seems to be the most promising one. To understand the details of this growth we have performed a suite of 8 N-body simulations in which merger times, mass ratios and orbital parameters were extracted from self-consistent cosmological simulations and reproduced in high-resolution, prepared mergers. Our simulations show that accretion of satellites is able to produce a growth in size by a factor of ˜4-6 and a growth in mass by a factor of ˜ 2; the growth in size occurs because satellite material is deposited in the outer part of the main galaxy. Thus, cosmological motivated dry minor mergers are sufficient to explain the size evolution of the massive elliptical galaxies.