This study examines the use of kulay(yo) as a response token in spontaneous Korean conversation. The data for the study include approximately five hours of Korean casual conversation and the analytic framework is conversation analysis. Based on its cooccurring prosody patterns, the use of kulay(yo) is divided into two types: the one with falling or continuing intonation and the other with upward intonation. The former type mainly occurs in acknowledgements, the identification and recognition sequence of phone openings, and phone preclosings and closings. The latter type is found in contexts such as informings, counterinformings, and interactionally delicate action sequences mainly as news receipts. The results show that kulay(yo) is used in various interactional contexts, reflecting how the recipient of the prior turn's talk deals with delicate actions and carefully marks his/her stance with it.