The SEOM/GEINO clinical guidelines provide recommendations for radiological, and molecular diagnosis, treatment and follow-up of adult patients with anaplastic gliomas (AG). We followed the 2016 WHO classification which specifies the major diagnostic/prognostic and predictive value of IDH1/IDH2 missense mutations and 1p/19q codeletions in AG. The diagnosis of anaplastic oligoastrocytoma is discouraged. Surgery, radiotherapy and chemotherapy with PCV or TMZ are the first-line standard of care for AG with slight modifications according to molecular variables. A multidisciplinary team is highly recommended in the management of these tumors.