Eggan first became well-known in anthropological circles for her remarkable portraits of anthropologists. After her marriage in 1969 to noted anthropologist and University of Chicago professor Fred Eggan, the range of subjects in her photography increased greatly. Eggan accompanied her husband on several of his research trips to the Philippines, Thailand, Indonesia, and England. Eggan documented these trips through photography, focusing on capturing images of local people and their everyday lives. Her photography was informed by her training as a psychotherapist: Eggan’s portraits often depict relationships between people, or focus on people going about their daily routines. Women and children were frequent subjects in her work.