Data regarding race and ethnicity are usually requested when conducting public health surveillance. However, such data are frequently not included in case reports by providers. This report describes efforts to reduce the extent of missing race and/or ethnicity data in reports of sexually transmitted diseases in Massachusetts. A list of cases reported to the Department of Public Health between March 1 and May 31 1999 lacking race and/or ethnicity data was generated. A student intern tried contacting the providers with a request for complete information. Of the 2,954 cases of syphilis, gonorrhea, and chlamydia infection reported during the study period, 34.8% (1,028 cases) lacked race/ethnicity data. Despite an average of 2.27 calls and 1.5 transfers per call, data was successfully added to only 143 cases, increasing the percent of reported cases with complete data from 65.2% to 70.0%. The telephone calls, while inefficient for collecting this data, had some advantages. For example, they offered opportunities for communication between the STD Division and providers regarding other provider needs or services that the Division might meet. Consideration can also be given to using surnmame lists, ethnic marketing lists, birth records, and matching the case's address with census block data to infer race and/or ethnicity.