The recommended diagnostic McDonald criteria after revision in 2005 are presented. The basis of criteria is demonstration of dissemination of lesions in both time and space. The diagnosis is made in grounds of clinical data with support of mainly MRI, but also results of cerebrospinal fluid examination and visual evoked potentials. There is new definition of MRI criteria to demonstrate dissemination of lesions in time what enables faster diagnosis of the disease. The role of detection of the spinal cord lesions was determined and in a new and simpler way criteria for primary progressive multiple sclerosis have been shown. Currently they require to demonstrate in this form of MS one year of disease progression plus two of the following: 1) nine T2 lesions or at least four T2 lesions with positive VEP; 2) at least two focal T2 lesions in spinal cord MRI; 3) positive CSF.