The contact resistance for the heat transfer between adjacent particles is identified as the limiting factor for heat transfer in moving beds of particles consisting of rather hard solid materials and filled with a stagnant interstitial gas. It defines the short time heat transfer, which is determined by the thermal conductivity of the gas between the heated surface and the first row of particles, as well as the long time heat transfer which is characterized by the progression of the temperature front into the bulk of the bed. It also governs the steady heat conduction through a stationary bed kept at different temperatures at its ends.