A new multiparameter lake assessment protocol, the Ohio Lake Condition Index (Ohio LCI), was developed by the State of Ohio to comply with the 305(b) guidelines in the Water Quality Act amendments of 1987. Thirteen in-lake parameters were assessed for each of Ohio's 417 publicly owned lakes. Both monitored data and evaluated information based on responses to a questionnaire were included in the assessment process. Raw data were transformed into subindex points for summation into a final numerical Lake Condition Index score. Sets of parameters were identified to determine whether or not designated uses and the goals of the Clean Water Act were being met. Applications of the Ohio Lake Condition Index are discussed, including using it to target lakes affected by nonpoint source pollution. The Lake Condition Index protocol can be modified to accommodate revisions to water quality standards and changes in a state's water quality management objectives for lakes. The authors question the appropriateness of reporting the status of lake condition based exclusively on the concept of trophic state.