This Masterʼs Thesis addresses the tools definition to collect and analyze the relevant information to research in prisons, from a cross-sector point of view, aimed to prevent and predict violent behavior in prisonʼs environment. Taking as starting point several qualitative methods, we discuss the suitability of them and we propose using biographical narrative method as the proper one for capturing relevant information about prison organization, inmates and professionals working in that context. To justify the suitability of the selected method mentioned above, an historical analysis of this method is included, as well as an updated view of its use in various research fields, particularly in prisons. For this purpose the violent behavior in inmates have been selected as exploration issue, considering its nature as element of offense and how it works in a prison environment. Finally, the design of a semi-structured interview is presented as proposed methodology for research in prison environment, based on for inmates in prisons.