D

• Defunct De Leonist parties in the United States(5 P)

S

• Socialist Labor Party of America(3 C, 15 P)
• Socialist Labour Party (UK, 1903)(1 C, 3 P)
• Syndicalist political parties(1 C, 15 P)

• De Leonism

I

• Industrial Workers of Great Britain
• International Socialist League

L

• League for Socialist Reconstruction
• League of Democratic Socialists

P

• Plebs' League

R

• Revolutionary Socialist Party (UK)

S

• Socialist Labor Party (Australia)
• Socialist Labor Party (Canada)
• Socialist Labour Party (UK, 1903)
• Socialist Party of Canada (WSM)
• Socialist Party of Great Britain
• Socialist Party of North America
• Socialist Trade and Labor Alliance

W

• Workers' International Industrial Union
• World Socialist Party (New Zealand)
• World Socialist Party of India
• World Socialist Party of the United States