Solidar Suisse is a Swiss non-profit organization with headquarters in Zurich. It also has a French-speaking Swiss branch in Lausanne and an association in Geneva, Solidar Suisse Genève. As an NGO, it fights for global justice and against extreme inequality. It campaigns for decent working conditions, democratic participation and social justice.

Solidar Suisse is the development organization that became organizationally independent from the Swiss Workers' Relief Association (SAH) in 2005 and was renamed Solidar Suisse in 2011.

In 1936, the Swiss Workers' Relief Organization was founded by the Swiss Trade Union Federation and the Social Democratic Party of Switzerland. Its purpose was to alleviate the effects of the Great Depression and to support workers' families in precarious situations in Switzerland and abroad, in part by funding holiday camps.

The organization soon became involved in Spain to help children who were victims of the Spanish Civil War. During the Second World War, the SAH distributed food parcels in refugee camps throughout Europe and cared for more than 2,000 refugees in Switzerland. In the immediate post-war period, the SAH provided emergency aid, social support and opened children's homes.

In 1949, the SAH was one of the first Swiss relief organizations to become involved in international development aid, working in Greece, Palestine/Israel, Yugoslavia and, after the Algerian War, in Algeria and Tunisia. In 1951, the SAH was also a founding member of the International Association for Workers' Relief (IAH), which was renamed SOLIDAR in 1995. The SAH supported political refugees from the Hungarian uprising, the Prague Spring, the Nigerian Civil War and the Greek junta. Since the 1970s, the SAH was involved in the solidarity movement for Central America, including Nicaragua. In the 1980s and 1990s, the SAH was also active in a large number of countries. In the 1980s, for example, it supported those persecuted by the Pinochet regime in Chile and was active in Bosnia and Kosovo during the Yugoslav wars (1991-2001), while maintaining its activities for the benefit of the population in Switzerland.

A dozen regional branches of the OSEO, however, continue to develop independently activities related to professional reintegration, training or the integration of migrant people  

In 2005, as part of a reorganization, the former foreign department of the SAH became an independent organization, although it continued to operate under the name Swiss Workers' Relief Organization. Even after the organizational separation, the organization continued its previous international development aid. For example, Solidar supported the victims of the devastating floods in Pakistan (2010).

In 2011, on the occasion of the 75th anniversary of the SAH, the organization was renamed Solidar Suisse, which in addition to the organizational separation also led to the separation of the name from the Swiss SAH associations. The name Solidar Suisse is based on the international network of the same name, SOLIDAR. After Typhoon Hayan (2013) in the Philippines, Solidar Suisse provided short-term emergency aid and was also involved in reconstruction for years. Solidar Suisse also provided emergency aid after the earthquake in Nepal in 2015, for the Rohingya refugees in Bangladesh in 2017, after the earthquake on the island of Sulawesi in 2018, after the Russian invasion of Ukraine and the floods in Pakistan in 2022, and after the earthquakes in Turkey and Syria in 2023.