BACKGROUND: Patient satisfaction is typically measured by quantitative surveys using predetermined domains. However, dissatisfaction may be an entity distinct from satisfaction, may have different determinants, and may better reflect problems in healthcare delivery. OBJECTIVE: The aim of this study was to describe domains of dissatisfaction experienced by patients during hospitalization. SETTING: The setting was a U.S. urban academic medical center. PATIENTS: The patients were adults discharged between July 1, 2007 and June 30, 2008 INTERVENTION: The intervention was a postdischarge telephone interview: "If there was one thing we could have done to improve your experience in the hospital, what would it have been?" MEASUREMENTS: The measurements were standard qualitative analysis of suggestions for improvement. RESULTS: We randomly selected 976 of 9,764 interviews. A total of 439/976 (45.0%) included at least one suggestion for improvement. We identified six major domains of dissatisfaction: ineptitude (7.7%), disrespect (6.1%), waits (15.8%), ineffective communication (7.4%), lack of environmental control (15.6%), and substandard amenities (6.9%). These domains corresponded to six implicit expectations for quality hospital care: safety, treatment with respect and dignity, minimized wait times, effective communication, control over physical surroundings, and high-quality amenities. Some of these expectations, such as for safe care, effective communication between providers, and lack of disrespect, may not be adequately captured in existing patient satisfaction assessments. CONCLUSIONS: The results represent patient-generated priorities for quality improvement in healthcare. These priorities are not all consistently represented in standard patient satisfaction surveys and quality improvement initiatives. Patient input is critical to assessing the quality of hospital care and to identifying areas for improvement. Journal of Hospital Medicine 2010;5:514-520 (C) 2010 Society of Hospital Medicine.