Green established the Opening the Archives Project at Brown University that has digitized, indexed, and made available to the public on an open-access website over 50,000 U.S. government documents about Brazil produced at the height of the Cold War during the Brazilian military dictatorship (1964–85).
He was active in the Service Employees International Union, Local 660 and co-founded the Lavender Caucus to defend LBGTQ+ workers’ rights, serving as its first co-coordinator.
Beyond Carnival: Male Homosexuality in Twentieth Century Brazil (University of Chicago), published in Portuguese in 2000 as "Além do Carnaval: a homossexualidade masculine no Brasil do século XX" (Editora da UNESP) with an expanded and revised Portuguese-language third edition in 2022.
In 2001, the Portuguese-language edition won the Cidadania em Respeito à Diversidade [Citizenship Respecting Diversity] Book Prize, awarded by the organizers of the São Paulo LGBT Pride Parade in 2001.
"Green manages to avoid the pitfalls of over-simplistic views, offering us new insights into struggles for dignity and recognition in a historical and cultural context that is characterized at once by its difference as well as by its multiple forms of structural violence and oppressions.
We Cannot Remain Silent: Opposition to the Brazilian Military (Duke University Press) published originally in 2009 in Portuguese as "Apesar de vocês: a oposição à ditadura militar nos Estados Unidos" (Companhia das Letras) Awarded the Book Work of Merit prize by the Brazil Section of the Latin American Studies Association in 2011.
44 (2012), 173-175 " At the time of writing this review, those opposed to US policy in Honduras have taken inspiration from We Cannot Remain Silent in their efforts to help restore the ousted president, Manuel Zelaya, to his full constitutional powers.
8 (2011), 1010-1011 " [A] well-written, engrossing, diligently researched volume is a sterling contribution to the literature on a neglected aspect of the fluctuating US-Brazilian relationship during 21 years (1964-85) of often harsh military rule."
72 (2011), 275-282 "Notable for its epistolary structure and multiple voices and [...] interspersed with explanatory narrative, it consists largely of the letters that flew backwards and forwards between Lina, working as an interpreter in Washington DC at the US State Department at the time of her son's detention, and Marcos's grandmother.
Featured in the first HAHR Open Forum and published in Portuguese as "“Quem é o macho que quer me matar?”: Homossexualidade masculina, masculinidade revolucionária e luta armada brasileira dos anos 1960 e 1970.
This collection of nine articles includes the chapter on homosexuality and the dictatorship written by the two editors for the final report of the National Truth Commission.
It received the Cidadania em Respeito à Diversidade [Citizenship Respecting Diversity] Book Award from the organizers of the São Paulo LGBT Pride March in 2015.
Portuguese edition, Revolucionario e Gay: A vida extraordinária de Herbert Daniel, a biography of a medical student, guerrilla fighter, and AIDS activist.
29 (2020), 290-292 " [Those] interested in the conflicts, strategies, and dilemmas of the Brazilian Left as it engaged in the struggle against the military regime will find in Green’s book a rich source of information.
56 (2019), E6-E7 "Green’s historical investigation enables him to reconstruct much of his life to paint a multidimensional picture of Daniel, who robbed banks, waxed poetic about film, and giggled at seemingly trivial comics with his fellow revolutionaries all while repressing his sexuality and assuming a painful celibacy throughout his young adulthood as he grew into a prolific writer and fierce activist for LGBTQ rights."
2nd ed., with Victoria Langland and Lilia Moritz Schwarcz (Duke University Press), a collection of 120 documents and commentaries on the history of Brazil.