This book consists of two parts. In Part One researchers will find a list of 1,750 place names, in alphabetical order, as recorded in the 1901 census returns for the city and county of Londonderry (also known as Derry). It includes the names in County Derry of all townlands, together with street listings for all towns. Against each place name (i.e., townland or town and street) is recorded the following information: District Electoral Division, Parish, Registrar District, Poor Law Union, and 17th-Century Landowner. Knowing the record jurisdictions for place names will result in more effective use of major Irish record sources such as 1901 and 1911 census returns; church registers; civil registers of births, marriages, and deaths; the national indexes to civil birth, marriage, and death registers; and estate records. Part Two, County Derry Parish Reports, features record sources--both civil and church--of value to family historians, compiled and recorded by parish.