RT Journal Article SR Electronic A1 Valeš, Miroslav T1 JF Romanica Olomucensia YR 2011 VO 23 IS 1 SP 31 OP 37 DO 10.5507/ro.2011.005 UL https://romanica.upol.cz/artkey/rom-201101-0005.php AB Standard ethical procedures, based on the informed consent, may result hardly applicable in vulnerable communities. In the same way the methodology of research encounters specific problems in these communities. Based on a personal experience gained during the research of Lakhota language revitalization in South Dakota and Shuar language in Ecuador, this paper intends to draw attention to some methodological problems and to the relativity of ethical criteria. Respectful treatment of participants in the research should be the primary preoccupation of any sociolinguist. For this reason, one of the main objectives of this paper is to propose some general rules to be considered when dealing with vulnerable communities.