not new. As early as 1898, Albert Neisser in Prussia, who discovered gonococcus, attempted to test serum therapy to prevent syphilis by injecting cell-free serum into patients, most of whom were prostitutes, without their knowledge and consent (Vollmann & Winau, 1996). Eventually some of those injected developed syphilis. Since the end of World War II, cutting ethical corners in human experimentation such as this has prompted the international community to call for protecting human research subjects and issuing ethical codes and regulations on the basis of informed consent (Nelson-Marten & Rich, 1999; Oddi & Cassidy, 1990). What kinds of rights do human beings have when they participate in research studies as subjects? What are researchers' moral and legal obligations toward their human subjects? How can researchers ensure the rights of human subjects are being protected? These questions become even more critical as the trend toward international collaborations in research increases (Wichman, Smith, Mills, & Sandler, 1997). To date, researchers in more than 100 countries in the world have collaborated with researchers in the United States. To extend scientific knowledge across countries is to simultaneously extend ethical sensitivity to all involved in research. To this end, this column explores ethical standards, their applications, and the challenges in protecting human subjects in an international arena.