Psoriasis is a chronic inflammatory skin disease affecting around 2-3 % of the population. The disease spectrum evolves from to the knees and elbows limited disease to erythrodermic psoriasis. The impact on the quality of life, the pruritus, the pain from palmo-plantar disease, arthropathic psoriasis and the comorbidities are the major complaints of the patients. The treatment relies on topical treatments with dermocorticosteroids with or without vitamin D derivatives, UVA or UVB phototherapy, conventional treatments including methotrexate, ciclosporin and acitretin, and, since around 15 years, biological treatments. The biological treatments for moderate to severe psoriasis progressed in a spectacular way with an improvement of clinical results and an amelioration of the safety profile at every step. This article discusses these developments from the TNF? antagonists, including etanercept, adalimumab and infliximab to the newly arrivals, the anti-IL17 and anti-IL23 antagonists, the anti-PDE-4 antagonists and the JAK inhibitors.