The illicit drug market in the United States not only moves large amounts of drugs around the country and abroad, it also transports a large amount of currency. During law enforcement interdiction investigations, officers inevitably encounter individuals who are in possession of large amounts of United States currency. Currency seizure investigations must abide by forfeiture law, putting restrictions on law enforcement. Law enforcement officials are compelled to prove that a criminal nexus exists and that the currency was the proceeds of illegal activity or was going to be used for illicit purposes. Additionally, all standards regarding police/citizen contact must be observed by officers upon the discovery of currency. The initial encounter between the officer and the suspect may happen under a variety of circumstances, come of which may not involve reasonable suspicion at the outset. After the discovery of large amounts of currency, officers must establish a criminal nexus associated with the currency. The first step toward this goal is establishing ownership of the money. Interview skills are of the utmost importance at this phase of the investigation. Once the ownership has been established, the officer must establish the origin of the currency; where it came from and how it was gained. Tips for investigating such questions are offered and include asking the suspect for telephone numbers for businesses or names they offer in their testimonials about the origins of the currency. Officers should also question suspects about the packaging and transportation of the currency. Once all this information has been gathered and analyzed by officers, a decision can be made regarding whether to seize the currency. Once currency has been seized, proper documentation becomes a crucial aspect of the case. Every element of the investigation must be fully and completely documented in an investigative report. Contact information for the authors is provided.