Abstract This paper intends to present applications of experimental charge density research in physics, chemistry and biology. It describes briefly most methods for modelling the charge density and calculating and analyzing derived properties (electrostatic potential, topological properties). These methods are illustrated through examples ranging from material science and coordination chemistry to biocrystallography, like the estimation of electrostatic energy in a zeolite-like material or the relation between electrostatic energy and spin density to macroscopic magnetic properties in a ferrimagnetic molecular material. The accurate structure and charge density of a coordination compound exhibiting LIESST effect is also described, together with an exemple of transferability of charge density methods to macromolecular science and protein crystallography.