Little is known about the value patients, physicians, and payers place on intangible attributes of care. Differences in valuations among these groups and misperceptions of value of intangible attributes to other groups can contribute to conflicts about treatment recommendations or coverage decisions. We surveyed patients, physicians, and managed care executives to assess their willingness to pay (WTP) for diagnostic certainty for peptic ulcer disease (PUD) and gastroesophageal reflux disease (GERD). To determine if patients, physicians, and payers accurately perceive each other's valuations of diagnostic certainty, participants were also asked to estimate the WTP of each of the other types of respondents. Patients were most likely, and executives least likely, to value diagnostic certainty. For PUD, 84% of patients, 61% of physicians, and 43% of executives expressed a positive WTP. Median WTP was low for all three groups ($1-9 for patients and physicians; $0 for payers). Physicians and executives both correctly predicted patient WTP. For GERD, 87% of patients, 52% of physicians, and 29% of executives expressed a positive WTP. Executives underestimated patient WTP. For both diseases, physicians' WTP was overestimated by patients and underestimated by executives. The inconsistency in the value that patients, physicians, and managed care executives place on diagnostic certainty indicates the potential for conflict over practice guidelines or access to services. WTP surveys can provide information to aid in anticipating and addressing areas of disagreement.