Considering the importance of institutional foodservice in modern dietary life and its influence on the environment, sustainable development in institutional foodservice industry carries great significance. The current study was conducted to investigate dietitians' perceptions of sustainable business-and-industry foodservice and their intentions to perform sustainable practices by applying a mixed methodology. For the quantitative study, an online survey was conducted on 362 dietitians who had worked at a contact foodservice company for more than 1 year. The survey was performed from December 15th, 2011 to January 30th, 2012, and 202 responses were used for the analysis. For the qualitative a study, a focus group interview was conducted during May, 2012 with representative employees of the company. According to the results, dietitians seemed to be unfamiliar with the terms "sustainability" or "sustainable development," whereas they understood related contents and practices. Dietitians' awareness and perceived need in terms of sustainable business-and-industry foodservice were not significantly different across general characteristics. Dietitians seemed to be highly aware of the impacts of business-and-industry foodservice on economy, whereas they appeared to lack understanding of its impacts on society and environment. Cost increase and levy on work in daily operations were considered as main obstacles hampering dietitians' intentions to perform sustainable practices. A total of 88.1% of responding dietitians expected that the meal price at a sustainable business-and-industry foodservice should be higher than the supposed standard price of 4,000 won, with an average reaching 5,270 won. Findings from this study could be used as baseline information for vitalizing sustainable business-and-industry foodservice in Korea.