Informed consent poses challenges in all settings. Challenges may be particularly great in international collaborative research, where cultural perspectives may differ, and where education levels and language may be barriers to participant understanding. We conducted a written survey and focus groups with US health researchers doing research in developing countries, asking about informed consent and other ethical issues in their research. We present here both qualitative and quantitative data relevant to informed consent. Qualitative data revealed that researchers' experiences and beliefs about informed consent fell into three paradigms: regulatory, community, and individual. The regulatory paradigm refers to researchers' views and practices relating to informed consent requirements of institutional review boards and other oversight bodies. The community paradigm refers to researchers' approach to the content and methodology of informed consent in the context of long-term relationships between research teams and study communities. Researchers emphasized the importance of these relationships for creating and maintaining communication fundamental to the informed consent process. Finally, the individual paradigm refers to researchers' views about individual participants' understanding and decision-making process regarding research. Researchers described community-level influences on participants' decision-making, but stressed the need for individual comprehension and voluntary participation. While these paradigms are distinct, they also are intertwined. Quantitative data supported the existence of these three paradigms in respondents' characterization of informed consent. Researchers frequently stated that legal language on the consent forms was meaningless (52%). Forty-four percent of researchers had consulted with community leaders, and 23% believed the consent process focuses too much on the individual, rather than on family or community. Most researchers (82%) reported that the consent process was an important means of educating participants about the study. Fifty-four percent of researchers believed participants did not understand placebos. Further research is needed to understand how culture and relationships affect research participation, and to provide information and dialogue among researchers, oversight bodies and community representatives about appropriate ways to approach informed consent in international research.