This review summarises the mechanisms underlying the efficacy of BRAF inhibitors in the treatment of BRAF-mutant melanoma, including their inhibitory effect on constitutively activated BRAF kinase and consequent interference with the MAPK pathway, and their immunomodulatory role in the tumour microenvironment, leading to enhanced tumour recognition by the immune system and anti-tumour T-cell responses. The gene discussed is BRAF; the disease is melanoma.