Psoriasis is a systemic chronic inflammatory disease associated with comorbidity. Many epidemiological studies have shown that psoriasis is associated with psoriatic arthritis as well as cardiovascular and metabolic diseases. Furthermore, obesity and psychological diseases such as depression and anxiety disorders are linked with psoriasis and play a central role in its management. The association of psoriasis and its comorbidity can be partly explained by genetic and pathophysiological mechanisms. Approximately 40 psoriasis susceptibility loci have been described with the majority linked to the innate and adaptive immune system. In some associated diseases, such as psoriatic arthritis, an overlap of their genetic susceptibility exists. Pathophysiologically the "psoriatic march" is a model that describes the development of metabolic and cardiovascular diseases due to the presence of underlying systemic inflammation. Dermatologists are the gatekeepers to treatment for patients with psoriasis. The early detection and the management of comorbidity is part of their responsibility. Concepts for the management of psoriasis and tools to screen for psoriatic comorbidity have been developed in order to support dermatologists in daily practice.