While international police cooperation and judicial cooperation in criminal matters were once perceived as two separate disciplines, the current escalation of international criminal activities has forced police and judicial cooperation to merge. Modern day investigations can no longer be carried out as they once were; increasingly sophisticated technologies and criminals have necessitated that police and judicial powers merge to allow investigations of criminal activities on the global level. Article 9 of the 1988 United Nations Convention on the enhancement of international law enforcement efforts is described as a precursor to bilateral and multilateral agreements on conducting international investigations. Following the 1988 Convention, many member states began contemplating the specific measures that would be considered special investigative measures to aid in the international investigation of transnational crimes. The Council of the European Union identified a number of special investigative categories, including cross-border observation, hot pursuit, and tracking. International developments during the 1990s that impacted special investigative techniques are reviewed and concerns over individual liberties are analyzed. In closing the author notes that law enforcement will always trail behind criminals, but with special investigative techniques at their disposal, law enforcement officials have a chance at keeping up. Footnotes