In addition, beginning in 1996, Retrospective Hugo Awards or "Retro-Hugos" have been available for works published 50, 75, or 100 years prior.
[4] Hugo Award nominees and winners are chosen by supporting or attending members of the annual World Science Fiction Convention, or Worldcon, and the presentation evening constitutes its central event.
The final selection process is defined in the World Science Fiction Society Constitution as instant-runoff voting with six nominees, except in the case of a tie.
Five authors have won three times: Isaac Asimov and Fritz Leiber (with two Hugos and one Retro-Hugo each), N. K. Jemisin, Connie Willis, and Vernor Vinge.
Three authors have won the award in consecutive years: Orson Scott Card (1986 and 1987), Lois McMaster Bujold (1991 and 1992), and N. K. Jemisin (2016, 2017, and 2018).