Finding them wasn't easy. Hate groups don't keep membership lists, but she had contacts from her earlier book. She also subscribed to hate literature, which she had mailed to a post office box. ''It was an unbelievable nightmare,'' Ms. Blee remembered. ''Going to the post office was so embarrassing. I'm sure they were horrified.''

Skinheads were particularly tough to reach, Ms. Blee said: ''It's not like they have an office.'' She contacted antigang task forces in police departments, which vouched for her. ''They lead marginal lives, their boyfriends beat them up,'' Ms. Blee explained. ''The police are often the only adults they can turn to, the one stable thing in their lives.''

Hate groups today are usually ''tiny and extremely marginal,'' she said, adding, ''After Oklahoma City, they became more subterranean, more dangerous, because the people who have remained are more hardcore, more interested in terrorist activities.''

But ''small is worse than large when you are talking about racism,'' Ms. Blee said. ''Bigger groups are easier to monitor.''

The neo-Nazi organizations tended to be stronger than Klan groups, she said: ''The Klan is xenophobic. Neo-Nazis are more open to Pan-Aryanism, which wants to unite Aryans around the globe.''

The groups had plenty of members who were women. Beginning in the 1980's, women have been actively recruited, because they are believed less likely to have criminal records and therefore to draw police attention.

Generally, women in hate groups were eager to be interviewed by Ms. Blee. She made it clear that while she didn't share their beliefs, she said, she wanted ''to give a fair and accurate portrayal of racist groups, and they liked that.'' Some had read her book on the Klan: ''They would say, 'I loved your book.' They felt it was fair. They are often caricatured in the media, and they liked being taken seriously.'' Besides, Ms. Blee said, ''their family and friends had given up on them.'' She continued, ''Being talked to by a professor was a big event.''