The intercalation of silver into layered semiconductors of III–VI family is investigated for the first time. Single crystals of indium selenide and indium sesquiselenide are intercalated by two methods: a classical electrochemical one and a pulsed electric field method. Kinetic parameters of the mobile ions (silver) were measured at room temperature. Low values of the chemical diffusion coefficient are observed and variations of D as a function of the silver concentration are presented.