The paper describes the unemployment insurance: its structural characteristics, its limits in solving its function and the principles which should inspire a possible reform. In particular, the Author focuses on the personal scope of protection and observes that the institute seems to be unsuited to the current labour market, in which precarious and discontinues jobs are increasing continuously. The social insurance structure cannot guarantee protection against unemployment to all workers, and this gives origin to unjustified discriminations (the exclusion of vertical part-timers is the best example). A proper reform has not been enacted by Parliament up to now, and the case law is not enough to fill the gaps. According to the Author, the rewriting of the social protection for the unemployed should be founded on the redefinition of involuntary unemployment, in accordance with the constitutional guidelines.