Doing ethnographic research can be exciting but also challenging for social scientists. Drawing from the experience of an ethnographic case study of a Korean diaspora community in Hanoi, Vietnam, this case study describes and analyzes some major themes of the ethnographic research process, including entering the field, ethics associated with gaining access to online groups, contexts in which the ethnographer conducting participant observation online, and a holistic approach in ethnography. Practical guidance for conducting successful participant observation online, especially in the study of another culture living in one's own culture are also offered.