The main aim of this work is to provide a set of tools for automatic segmentation of Italian speech into phones. We make available already trained acoustic models, a compiled version of the automatic aligner, a script to convert the segmentation into PRAAT format and the necessary documentation. The acoustic models have been trained with the SPRAAK toolkit, using HMMs extracted from the CLIPS corpus. In order to evaluate performances, first of all we measured phone markers distances between our segmentation and a reference one, using both a test corpus and the APASCI database. Then we also compared the results of metrics applied to manual and automatic segmentations in the frame of an independent study on Neapolitan Italian prosody. Our results show that the automatic alignment provided by ASSI is a fast and reliable substitute for manual segmentation in lab-speech based linguistic studies.