Participants will have a complete medical and dental history. Saliva samples will be collected from the major salivary glands, which are located in the cheeks and under the jaw. Several blood samples will also be drawn for tests. Some patients will have a biopsy of the minor salivary glands, usually from the lower lip, to confirm or rule out the diagnosis of Sjogren's syndrome and determine the extent of changes in the salivary glands. The ability to taste and smell may also be evaluated, and patients may have an ultrasound examination of their swallowing function.