Frontotemporal dementia and Parkinsonism linked to chromosome 17 (FTDP-17) is a congenital degenerative disease of the central nervous system. Molecular genetics studies have indicated the presence of 26 various mutations of the tau protein gene. At present 61 families with this syndrome are known. The clinical criteria proposed in this paper were developed on the grounds of the author's own research as well as detailed review of the literature. The criteria include;--clinical symptoms: personality and behavior disorders, Parkinsonism rather resistant to treatment with Levodopa less frequently also speech disorders and epilepsy,--an early onset and rapid progression of the disease,--positive family history,--heterogeneity of clinical symptoms both among patients within the same family and among families with the same mutation,--heterogeneity of the clinical picture depending on the type of mutation. Although FTDP-17 is and extremely rare clinical syndrome, it is noted all over the world. In Poland nobody has been diagnosed with this condition yet. The aim of this paper is to acquaint the readers of Neurologia i Neurochirurgia Polska with the FTDP-17. The syndrome has considerably contributed to our understanding of pathogenesis of many sporadic degenerative diseases of the brain, including such frequent conditions as Alzheimer's disease, Pick's disease the the Steel-Richardson-Olszewski syndrome, corticobasal degeneration, and other ones. Undoubtedly further research into the FTDP-17 will contribute to the development of a successful treatment for these devastating degenerative diseases of the c.n.s.