SUMMARYComplement components C3a, C4a, and C5a, were assayed in corneal scale extracts from psoriasis and other dermatoses characterized by sterile subcorneal pustules, using radioimmunoassay. Larger amounts were detected in psoriasis and related pustular dermatoses than in extracts of non‐inflammatory stratum corneum. It is concluded that complement is activated via the classical pathway and releases the neutrophil chemotactic fragment C5