The facilitated transport of americium(III) (Am(III)) through a supported liquid membrane (SLM) impregnated with dimethyldibutyltetradecyl-1,3-malonamide (DMDBTDMA) in n-dodecane has been studied. Microporous PTFE membrane was used as the polymeric support. Am-241 tracer in nitrate medium constituted the feed phase and 0.01 M nitric acid was used as the strip phase. A model describing the transport mechanism which considers all possible transport resistances has been proposed. An attempt has been made to explain the experimental data quantitatively with the help of wellknown diffusion rate equations. The chemical conditions and diffusional parameters affecting transport have been investigated. Under identical conditions, permeability of Fe(III) is found to be significantly lower than that of Am(III). Durability/chemical stability of the membranes has also been studied.