Counterfeit drugs (also known as “fake or falsified medicines”) have become a major world-wide public health concern. Falsified medicines may contain toxic substances, the wrong active ingredients, suboptimal amounts of active ingredients, or no active ingredients at all. CDC researchers developed a portable (handheld), battery-operated, and relatively inexpensive device that non-trained personnel can use quickly to evaluate a particular branded tablet for authenticity. The low-cost and simple-to-use CoDI can aid the general public as well as hospitals, clinics, and pharmacies to assess drug quality. The CoDI does not require the use of consumables such as solvents or chemicals, and does not destroy the sample. Thus, the device is safe to use and allows the samples to be available for subsequent analysis if necessary. The CoDI can benefit drug regulatory, Customs and law enforcement agencies for testing and screening large amounts of samples. CoDI provides instantaneous results that can allow agencies to rapidly begin searching for counterfeit drug sources and implement intervening measures to stem the production and availability of counterfeit drugs. CDC researchers successfully tested the CoDI prototype in Ghana on a project to detect falsified, degraded, and expired ingredients in antimalarial tablets. Field trials to test additional drug samples are underway. Matchbook sized versions with yes/no indicator lights are being developed for specific brands. These are even simpler to use and lessen any chance of operator error.