The following year, she began working as a volunteer in the Guyana National Service (GNS), an organization that provided basic training and skills for unemployed youth.
She pursued studies at the University of Guyana between 1976 and 1977 while continuing her employment in the library, and became active in promoting the film The Terror and the Time, a documentary on British colonialism.
In 1979, after an investigation into whether Working People's Alliance members had involvement with a recent arson, her home was searched and she was charged with larceny for some material found concerning the GNS.
Initially their efforts focused on education and political rights, but in 1993, de Souza disaffiliated with the WPA, becoming a full-time coordinator for Red Thread.
[1] De Souza has done research on prostitution and sex work in Guyana,[3] as well as participated in conferences on critical geography to evaluate how location intersects with socio-political factors, such as class, ethnicity, gender, nationality, race and sexuality.
She coordinates efforts with the judiciary and the Guyana Police Force to educate and understand the complex issues surrounding domestic violence,[1] building bridges for quick action when situations arise.