Existing studies in dialogue system research mostly treat task-oriented dialogue and chitchat as separate domains. Towards building a human-like assistant that can converse naturally and seamlessly with users, it is important to build a dialogue system that conducts both types of conversations effectively. In this work, we investigate how task-oriented dialogue and knowledge-grounded chit-chat can be effectively integrated into a single model. To this end, we create a new dataset, KETOD (Knowledge-Enriched Task-Oriented Dialogue), where we naturally enrich taskoriented dialogues with chit-chat based on relevant entity knowledge. We also propose two new models, SimpleToDPlus and Combiner, for the proposed task. Experimental results on both automatic and human evaluations show that the proposed methods can significantly improve the performance in knowledge-enriched response generation while maintaining a competitive task-oriented dialog performance. We believe our new dataset will be a valuable resource for future studies. Our dataset and code are publicly available 1 . * Work done as a research intern at Meta. 1 https://github.com/facebookresearch/ ketod) I would like to see a Musical show. system user I would like to find an event around SD. What type of event do you prefer? KETOD Alejandro Sanz is at Cal Coast Credit Union Amphitheater on March 7th at 7:30 pm. He is known for flamenco-influenced ballads, but experiments with other genres too, it's sure to be a good show! Knowledge from Wikipedia Alejandro Sánchez Pizarro, better known as Alejandro Sanz born December 18, 1968), is a Spanish musician, singer and composer. … The singer is notable for his flamenco-influenced ballads, and has also experimented with several other genres including pop, rock, funk, R&B and jazz.system user