This paper presents a methodology to audit the functioning of an organizational intelligence system that covers all human, informational, technological and procedural elements involved. The methodological process is based in a triangulation of data, qualitative techniques and perspectives, organized in three phases: exploratory, intermediate and focused. A literature review, a participant observation and a case study in the intelligence department of a Spanish private security company are carried out. The results enabled the authors to propose the preference for an operational advisory audit, the operational principles, the procedures to define priority elements and aspects to be audited, the stages and the activities to be carried out, and the techniques and instruments for the collection and analysis of information. The intelligence audit makes it possible to identify the active elements and the relevant actions in the intelligence system and understand how they function within the framework of their relationships with the organization to which it belongs and its environment. The intelligence system should be audited by paying attention to strategic business processes and taking into account the organizational structure, procedures, culture and information behaviour involved. The proposed intelligence audit can be applied to the planning and assessment of any kind of organization due to its comprehensiveness and flexibility