Effective patient-provider communication is a critical aspect of the delivery of high-quality patient care; however, research regarding the conversational dynamics of an overall emergency department (ED) visit remains unexplored. Identifying both patterns and relative frequency of utterances within these interactions will help guide future efforts to improve the communication between patients and providers within the ED setting. The objective of this study was to analyze complete audio recordings of ED visits to characterize these conversations and to determine the proportion of the conversation spent on different functional categories of communication. Patients at an urban academic ED with four diagnoses (ankle sprain, back pain, head injury, and laceration) were recruited to have their ED visits audio recorded from the time of room placement until discharge. Patients were excluded if they were age < 18 years, were non-English-speaking, had significant history of psychiatric disease or cognitive impairment, or were medically unstable. Audio editing was performed to remove all silent downtime and non-patient-provider conversations. Audiotapes were analyzed using the Roter Interaction Analysis System (RIAS). RIAS is the most widely used medical interaction analysis system; coders assign each "utterance" (or complete thought) spoken by the patient or provider to one of 41 mutually exclusive and exhaustive categories. Descriptive statistics were calculated for all 41 categories and then grouped according to RIAS standards for "functional groupings." The percentage of total utterances in each functional grouping is reported. Twenty-six audio recordings were analyzed. Patient participants had a mean (±SD) age of 38.8 (±16.0) years, and 30.8% were male. Intercoder reliability was good, with mean intercoder correlations of 0.76 and 0.67 for all categories of provider and patient talk, respectively. Providers accounted for the majority of the conversation in the tapes (median = 239 utterances, interquartile range [IQR] = 168 to 308) compared to patients (median = 145 utterances, IQR = 80 to 198). Providers' utterances focused most on patient education and counseling (34%), followed by patient facilitation and activation (e.g., orienting the patient to the next steps in the ED or asking if the patient understood; 30%). Approximately 15% of the provider talk was spent on data gathering, with the majority (86%) focusing on biomedical topics rather than psychosocial topics (14%). Building a relationship with the patient (e.g., social talk, jokes/laughter, showing approval, or empathetic statements) constituted 22% of providers' talk. Patients' conversation was mainly focused in two areas: information giving (47% of patient utterances: 83% biomedical, 17% psychosocial) and building a relationship (45% of patient utterances). Only 5% of patients' utterances were devoted to question asking. Patient-centeredness scores were low. In this sample, both providers and patients spent a significant portion of their talk time providing information to one another, as might be expected in the fast-paced ED setting. Less expected was the result that a large percentage of both provider and patient utterances focused on relationship building, despite the lack of traditional, longitudinal provider-patient relationships.