We reviewed 62 cases (26 men and 36 women, median age 55 years) of previously diagnosed lichenoid dermatitis and correlated the histologic and immunodermatologic findings with the clinical diagnosis and course. The clinical diagnostic groups were contact dermatitis (6 cases), drug eruption (14), lupus erythematosus (6), lichen planus (3), cutaneous T cell lymphoma (3), chronic dermatitis or neurodermatitis (19), and miscellaneous dermatologic disorders (11). With the use of individual histologic features, a correlation with specific clinical conditions was possible, and the clinical groups of dermatitis, drug eruption, lupus erythematosus or lichen planus, and T cell infiltration could be selected histologically. Direct immunofluorescence studies were of most help in the diagnosis of lupus erythematosus and atypical lichen planus, but these studies should be performed in all cases involving lichenoid inflammation. Although previously the nonspecific term lichenoid dermatitis was used to classify the histologic features in these cases, we found that by careful correlation of histologic, immunodermatologic, and clinical features, we were often able to provide a specific diagnosis.