Abstract. Migrating cells measure the external environment through receptorbinding of specific chemicals at their outer cell membrane. In this paper this non-local sampling is incorporated into a chemotactic model. The existence of global bounded solutions of the non-local model is proven for bounded and unbounded domains in any space dimension. According to a recent classification of spikes and plateaus, it is shown that steady state solutions cannot be of spike-type. Finally, numerical simulations support the theoretical results, illustrating the ability of the model to give rise to pattern formation. Some biologically relevant extensions of the model are also considered.1. Introduction. Chemotaxis, the active orientation of cells and organisms along chemical gradients, plays a crucial role in many biological processes, including embryonic development, immunology and cancer growth. Accordingly, a vast amount of research, both experimental and theoretical, has been devoted to understanding the mechanistic basis of chemotaxis.In 1953, Patlak [28] introduced the first mathematical model for chemotaxis. A similar model was derived by Keller and Segel in 1970 [16], albeit under different assumptions. These pioneering works have initiated an intensive mathematical investigation of the Patlak-Keller-Segel (PKS) model over the last 30 years. Of particular interest is the following special case, which we refer to as the classical chemotaxis model: