Clinical assessment of burns is accurate for very deep and very shallow burns, but it has been suggested that there is a high degree of inaccuracy in the assessment of dermal burns. Histologic analysis has, by some, been considered too time-consuming for routine diagnosis. It also requires an expert skin histopathologist to categorize the depth. With the use of an in vitro model, we have found the use of cryosections and an immunofluorescent staining method to be quicker and more clear-cut than standard light microscopic techniques. We believe this method plays a role in helping to define burns that would benefit from early excision and grafting. However, further investigation is required to transform the method from an experimental model to standard practice in the clinical setting. (J Burn Care Rehabil 1999;20:207–11)