The Transgender Day of Remembrance (TDoR), also known as the International Transgender Day of Remembrance, is observed annually on November 20 as a day to memorialize those who have been murdered as a result of transphobia and to draw attention to the continued violence endured by the transgender community.

Transgender Day of Remembrance was founded in 1999 by Gwendolyn Ann Smith, a transgender woman, to memorialize the murder of transgender woman Rita Hester in Allston, Massachusetts. Since its inception, TDoR has been held annually on November 20, and it has slowly evolved from the web-based project started by Smith into an international day of action. In 2010, TDoR was observed in over 185 cities throughout more than 20 countries.

以上資料來自：https://en.wikipedia.org/wiki/Transgender_Day_of_Remembrance