The authors introduce the construct of I-sharing--the belief that one shares an identical subjective experience with another person--and the role it plays in liking. In Studies 1-3, participants indicated their liking for an objectively similar and an objectively dissimilar person, one of whom I-shared with them and the other of whom did not. Participants preferred the objectively similar person but only when that person I-shared with them. Studies 4 and 5 highlight the role that feelings of existential isolation and the need for closeness play in people's attraction to I-sharers. In Study 4, people with high needs for interpersonal closeness responded to I-sharers and non-I-sharers with great intensity. In Study 5, priming participants with feelings of existential isolation increased their liking for I-sharers over objectively similar others. The results highlight the importance of shared subjective experience and have implications for interpersonal and intergroup processes.