Regionale Diakonie Wiesbaden Rheingau-Taunus, with its headquarters at Rheinstraße 65, is part of Regionale Diakonie in Hessen und Nassau gGmbH. It is a member organization of Diakonie Hessen and thus of Diakonie Deutschland, the social service of the Protestant Church.

Diakonie began its work in Wiesbaden in 1962 as a "care association". People seeking help were assisted with visits to the authorities or doctors, for example. At the same time, "Meals on Wheels" was launched to help the elderly, which was expanded to include "Home Help" in 1978. The specialist dementia advice service has been continuously expanded since 2001 and today also includes care and leisure activities.

In 1970, the "House for Mother and Child" was opened, which now provides socio-educational support for young single parents as a "Residential community for mother/father and child". In 1986, the "Women's Shelter", the Center for Counselling and Therapy (ZBT) and the "Teestube" were added. Today, it is still an important contact point for homeless people and part of the emergency housing assistance network, which also includes street social work, the "transitional home", outpatient everyday assistance (assisted living) with various facilities and advice for adult immigrants and people from Eastern Europe. Diakonie has also been running a debt counseling service since 2005. In recent years, the neighborhood office and the KinderElternZentrum (KiEZ) in the Biebrich/Gräselberg district have been added.

Since 2022, the former "Diakonisches Werk" has been operating under the name "Regionale Diakonie", and since 2025, Regionale Diakonie has united the services in Wiesbaden and the Rheingau-Taunus district under one roof. In addition to counseling, the focus there is on services for mentally ill people and youth welfare. The Regional Diakonie also coordinates the food banks in Untertaunus and the "Klamottenglück" clothing store in Idstein.

Around 180 employees and several hundred volunteers are involved in the Regional Diakonie Wiesbaden Rheingau-Taunus in 2025. The services are open to everyone, regardless of nationality, religion or social status.