Our IT world today is facing de-perimeterisation, a term used by the Jericho Forum to represent the breaking down of the traditional network perimeters that protects an organisation’s internal network from external threats.  This is due to highly connected inter-networks, proliferation of remote workers, outsourcing & partnership caused by changing business models and the weakening ofthe firewalls because of the numerous “holes” punched by new applications.  There is without doubt that de-perimeterisation is happening and it brings many threats to organisations.  One such organisation is a law enforcement agency which is the authority to fight against crime.  Equipped with high-tech equipment and using latest advanced systems, the law enforcement agency has relied quite heavily on IT to assist it in its day-to-day operations.  In face of budget constraints and with implementations of cost-cutting measures, the law enforcement agency is not spared the effects of de-perimeterisation and is also facing threats associated with de-perimeterisation.  The understanding of these threats, analysing them and proposing countermeasures and recommendations to mitigate the risks are the focus of this study.