Abstract
The complement system comprises a group of plasma proteins which play a central role in the development of immunologically-induced inflammation. The topics discussed included; the classical and alternative pathways of complement reaction sequences; phlogistic products of complement activation, modulation of complement activation by intrinsic control mechanisms; mechanisms of hypocomplementemia; decreased synthesis in genetic deficiency of complement components; and complement in systemic lupus erythematosus and rheumatoid arthritis and in glomerulonephritis.