%X In the following contribution an innovative two step strategy for the inversion of amplitude-only data in microwave imaging applications is presented. At the first step an inverse source problem is solved for computing the incident field in the investigation domain. Then, in the successive step, an iterative multi-resolution method combined with an evolutionary optimiser is applied in order to extract the reduced amount of information of the problem at hand. Some numerical and experimental results show the effectiveness and the limit of this technique. This is the author's version of the final version available at IEEE. %D 2011 %L elediasc12314 %I University of Trento %A Gabriele Franceschini %A Davide Franceschini %A Massimo Donelli %A Renzo Azaro %A Andrea Massa %T Electromagnetic Inversion of Amplitude-Only Data Through a Two-Step Strategy