"I was going to put Stop the Outrageous Abuse of Our Fellow Magical Creatures and Campaign for a Change in Their Legal Status - but it wouldn't fit. So that's the heading of our manifesto."
-- Hermione Granger (GF14)
The Society for the Promotion of Elfish Welfare, or S.P.E.W, was an organization founded in 1994 by Hermione Granger in response to what she saw as gross injustice in the treatment of house-elves. When she founded the society, Hermione appointed Ron as treasurer and Harry as secretary (GF14). A few people joined, like Neville (GF15), but many including Fred, George, and Hagrid, refused (GF16). The Society didn’t exactly catch on among Hogwarts students, but she persevered. Eventually (fall of 1995) she started knitting hats and socks which she left lying around Gryffindor tower, hoping to free some unsuspecting elf who picked them up while cleaning the common room. Once the elves discovered the hidden garments, they were deeply offended and refused to clean Gryffindor Tower anymore. Dobby picked up the slack, doing all the cleaning himself. After finishing her studies at Hogwarts in 1999, Hermione took a position with the Ministry of Magic where she worked to improve the lives of house-elves and other magical creatures (BLC).
Rowling said about S.P.E.W. and Hermione's efforts to improve the lot of House-elves:
Hermione began her post-Hogwarts career at the Department for the Regulation and Control of Magical Creatures where she was instrumental in greatly improving life for house-elves and their ilk. She then moved (despite her jibe to Scrimgeour) to the Dept. of Magical Law Enforcement where she was a progressive voice who ensured the eradication of oppressive, pro-pureblood laws (BLC).