To date, relatively little effort has been expended on revitalizing sign languages. To understand the current vitality of sign languages, it is important to distinguish two sociolinguistic types of sign languages. The better-known type can be termed Deaf communities, typically urban and national in character. Alongside these are shared-signing communities, typically in rural areas with a high incidence of hereditary deafness, in which many hearing people actively use the sign language in addition to deaf people. These two types differ in patterns of intergenerational transmission and language loss. Although we can be cautiously optimistic about the future of Deaf community languages, shared-signing communities are facing massive erosion already. To date, most attempts to strengthen sign languages have focused on supporting continued use of Deaf community languages; efforts to support and even revitalize dying shared-signing communities have only just begun.