Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Polymer latexes have many industrial applications and are considered as models of colloids. The DLVO theory has been widely used to describe the colloidal stability. The adsorption of Ni2+ and Fe3+ cations on polyvinyl acetate latex particles in the presence of NO3- counterions, and the colloidal stability of the system were studied. The obtained results indicate that Ni2+ or Fe3+ cations were adsorbed on the latex particles' hairy layers, which also helped to prevent latex coagulation. The stability of the PVAc latex within highly concentrated ionic media shows a deviation from the behavior described by the classical DLVO theory.3341699171176Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)