We examine whether psychological contract theory and social response theory can explain users' responses to e-commerce recommendation agents (RAs). Theories of social response to technology, trust in technology, and technology adoption are used to adapt psychological contract theory to explain user-RA relationship. We theorize that a psychological contract breach will cause a negative emotional reaction, called a psychological contract violation, which, via trust and usefulness perceptions, will influence users' intentions to follow an RAs' recommendation. We tested our theory using a sample of 426 participants across three studies. Using a sample of 103 participants, Study 1 elicited perceived user-RA obligations, which form the basis for the posited psychological contract. Using a sample of 102 participants, Study 2 demonstrated a significant effect of breaching these obligations on theorized emotional, cognitive, and behavioral reactions to the RA using experimental RAs. Using a sample of 221 subjects, Study 3 confirmed our findings.