Atopic dermatitis is a chronic, pruritic, relapsing inflammatory disease with a complex etiopathogenesis. Alterations of the epidermal barrier function together with a predominantly type 2 altered immune response are responsible for the heterogeneous clinical manifestation. Although pruritic eczematous plaques represent the most frequent phenotype, several others are also characteristic. The diagnostic of the disease relies on clinical aspects, and no complimentary tests are needed. In the literature, we can find a significant number of diagnostic and screening biomarkers; however, severity ones are the most reliable and applicable. Patient-tailored treatment is mandatory, as not all the patients equally respond to the same drugs. The newly released therapies, as well as those under investigation, give hope to AD patients.