In this paper it is intended to discuss some of the names of islands and other features of Lough Ree. Basic methodologies employed in the study of Irish toponymy as well as the linguistic shift from Irish to English in the area during the 18th and 19th centuries will be touched upon by way of background. Lough Ree is divided between three counties, Roscommon, Longford and Westmeath, with most of the larger islands being in either Longford or Westmeath. Some hundreds of placenames are recorded on the Ordnance Survey first edition maps of the lake (c. 80 are recorded in the portion in Co. Westmeath alone). Field work carried out on the island of Inchturk, Co. Westmeath, indicates the likelihood that many more are known locally, and remain unrecorded. (It will not be possible to examine each and every placename in this paper.) A general survey of the placenames of the lake will reveal, for example, the relatively early date of many names of the larger islands as compared to adjacent townland names; light will also be shed on local Irish dialect features, and language shift in the area. For the purposes of this survey the placenames of Lough Ree will be assigned to three categories: (1) Early attested names of the larger islands (which are usually also townlands, and many of which were inhabited until recent times); (2) Smaller island and minor shoreline feature names which are apparently later in date, and exhibit dialect features of the Irish formerly spoken in the area; (3) English language navigational and feature names which have their origins in the 18th and 19th centuries.