Masters and Johnson in St. Louis
Virginia E. Johnson was hired by William H. Masters as a research assistant at Washington University in the mid 50's, and the two began a long research career. Masters and Johnson were not perfect, but I have some mad love for what they have contributed to the understanding of sexual functioning - particularly female sexual functioning. These were the first people to actually observe and record physical sexual response in males and females. No more did people have to guess about things like where vaginal lubrication came from. They gave the scientific community actual physical data from which to begin understanding sexuality in humans. They showed us how similar the male and female pleasure cycle and orgasm actually were. In a time obsessed with the Freudian idea of a "mature" vaginal orgasm and an "immature" clitoral orgasm, they showed us that there weren't several types of female orgasms - just one - just like men. They also sparked a whole new type of therapy to deal with sexual problems.
Now, like I said, they weren't perfect though. They went about their research and therapy with the idea that women should be able to have orgasms through intercourse alone (even though their research showed that orgasms through intercourse, which few women were able to have, were actually due to indirect clitoral stimulation and were some of the weakest orgasms they recorded). They also had a program from 1968 to 1977 at the Masters and Johnson Institute to make homosexuals heterosexual. So...they could have been more progressive, but what they did do right was significant and important.