The impact of liquid drops with a solid surface has been studied as basic research on jet impingement and for applications in ink-jet printing. However, accurate information is still missing about the physics of the relevant phenomena for the case where multiple droplets impinge successively onto a solid, which is a quite frequent phenomenon in ink-jet printing.The present study considers the impact of single and two successive drops onto a solid surface with special emphasis on the following situation: the leading drop impinges onto the dry solid surface and comes to rest after eventual oscillations with a given contact angle depending on the interactions between the fluid and the substrate; the incoming drop then impacts onto the top of the previous droplet in an axisymmetric manner. The preliminary experiments performed at low velocities show that after coalescence of the two drops, the swelling behavior and oscillations of the liquid mass is very much alike to the case of a single drop of larger size.The experimental methods used to study the relevant phenomena are based on high speed cinematography and phase controlled ultra short snap shots of the impact process. A range of flow regimes is covered with the occurrence of spreading, retraction and oscillation of the liquid mass. The above mentioned devices allow to observe in detail the large deformations experienced by the drops over very small time scales, the encapsulation of the incoming drop by the static one, the propagation of instabilities on the liquid mass and the eventual recoiling of the drops.Finally, the different results that have been obtained are compared with existing data, the possible physical mechanisms are pinpointed and explained and a unified framework of the impact process taking into account the image quality on substrates during actual ink-jet printing is suggested.