Systemic lupus erythematosus (SLE) is a chronic systemic autoimmune disease that causes multi-organ damage and significant morbidity and mortality. Various efforts have been made to modulate the imbalanced immune responses in this disease. The manipulation of the immune system through the use of soluble synthetic peptides serving as antigenic epitopes, in repeated doses, has been shown to induce immune tolerance and to reduce the clinical manifestations of the disease in murine models. Although clinical trials in humans with the anti-DNA Ig peptide hCDR1 have failed, recent results from a clinical trial with another peptide, p140, have shown promise. This review provides an overview on the preclinical and translational work with synthetic peptides in SLE.