This paper deals with a theoretical investigation of the peristaltic transport of a Williamson nanofluid in a tapered asymmetric channel under the action of a thermal radiation parameter. In general, the nanofluids are electrically conducting nature. A model of wall-induced fluid flow within an infinite tapered channel has been developed to simulate the transport phenomena due to asymmetric wall displacements. This problem has plentiful applications. Moreover, it may serve as a model for the intrauterine fluid motion in a sagittal cross-section of the uterus under cancer therapy and drug analysis. The analytical solution has been obtained for the temperature and concentration of the nanofluid. The expressions for the axial velocity, stream function and pressure gradient were also obtained by a regular perturbation technique. Numerical computations have been performed for the pressure rise and the effect of various emerging parameters on the flow characteristics are shown and discussed with the help of graphs. The numerical results shown that the trapped bolus was increased in size and more trapped bolus were also occurred near the right wall with increasing Weissenberg number and thermophoresis parameter but that got decreased for large values of local temperature Grashof number. (C) 2014 Elsevier Ltd. All rights reserved.