A study group of the European Society of Cutaneous Lupus Erythematosus (EUSCLE) developed a Core Set Questionnaire for the evaluation of patients with cutaneous lupus erythematosus (CLE). The aim of the EUSCLE Core Set Questionnaire is to gain a broad and comparable data collection of patients with CLE from different European centers, to achieve consensus concerning evidence-based clinical standards for disease assessment, and to develop diagnostic and therapeutic guidelines. The authors designed the EUSCLE Core Set Questionnaire by including parameters considered most relevant for the evaluation of CLE and compiled from international literature, clinical praxis, and long-term experience with this disease. The compilation of the different parameters for the evaluation of CLE resulted in the 4-sided EUSCLE Core Set Questionnaire with six sections on patient data, diagnosis, skin involvement, activity and damage of disease, laboratory analysis, and treatment. Thus, the EUSCLE Core Set Questionnaire for CLE constitutes a useful tool for the collection and evaluation of epidemiological data from patients with this disease. It enables consistent statistical evaluation, exchange, and comparison of patient's data within several European countries and provides a set of guidelines for standardized diagnostic and therapeutic strategies in CLE.