It's difficult to convince some people that markets tend to weed out discrimination, or at least penalize those who discriminate. For example, let's say that Ty and Amy, a male and female carpenter, respectively, can both produce four shelving units in a week. If Ty is the favored party and earns, say, $1,000 per week, while Amy, the disfavored party, earns only $800 per week, then why aren't more Amy's hired and fewer Ty's? The marginal cost for Amy to produce a bookshelf unit is $200, while for Ty it's $250, and if profit maximizing firms in a competitive market don't act on this cost differential, they're not likely to remain in business for long. Or at least they'll pay in the form or reduced profits.
But many people see discrimination in various forms in the workplace and chalk it up to problems with markets, which require workplace regulation to advance the interests of those discriminated against. The problem, however, is that when you impose such regulations firms work around them, much to the detriment of those such regulations profess to help. If someone can sue for discrimination, you can bet that fewer firms will be willing to hire them, thus driving down their wages. And mandating quotas simply alters whom I hire. Since lesser skilled people tend to not advance much in the workplace, and are consequently more likely to sue their employer for discrimination, firms respond by hiring fewer workers with standing to sue who also have lower skills.
The problem of workplace discrimination comes about for other reasons, one that I refer to as the Happy Meal effect. A year or so ago my kids got McDonald's Happy Meals. The meals came in boxes that had on two sides a game for boys and on the other two sides a game for girls. The boy's side contained such directives as (and I'm paraphrasing), "You found the secret hiding spot, move ahead two spaces." or "You discovered your opponents secret, move ahead one space." The girl's game had such gems as "OMG, you and another girl wore the same dress to a party, go back one space." and "Curling Iron burnout, go back two spaces."
Boys are problem solvers - they should be creative, adventurous, and inquisitive, all traits respected in a business setting. Girls on the other hand, are baubels - they should just sit on the side and look pretty, traits that are not necessarily respected in a business setting, at least not in positions of authority.
Consider the reaction most people have when a male superior berates an employee for making a mistake or acting in some unacceptable manner. Traditionally, the superior is feared and respected. But if it's a female superior acting the same way, the reaction is often to refer to her as "a bitch."
Some good studies are exploring this problem, including this study.
Victoria Brescoll, a researcher at Yale, made headlines this August with her findings that while men gain stature and clout by expressing anger, women who express it are seen as being out of control, and lose stature. Study participants were shown videos of a job interview, after which they were asked to rate the applicant and choose their salary. The videos were identical but for two variables — in some the applicants were male and others female, and the applicant expressed either anger or sadness about having lost an account after a colleague arrived late to an important meeting.
The participants were most impressed with the angry man, followed by the sad woman, then the sad man, and finally, at the bottom of the list, the angry woman. The average salary assigned to the angry man was nearly $38,000 while the angry woman received an average of only $23,000.
When the scenario was tweaked and the applicant went on to expand upon his or her anger — explaining that the co-worker had lied and said he had directions to the meeting — participants were somewhat forgiving, giving women who explained their anger more money than those who had no excuse (but still less money than comparative men).
So the cause behind discrimination is not necessarily a market problem as much as it is a cultural problem. If women are perceived as lacking competitiveness (or actually do lack competitiveness due, in part, to having it instilled in their heads since childhood that to problem solve is for boys and girls should simply look pretty and not act aggressively) or the ability to effectively manage people, then they'll be overlooked for management positions. Regulating the labor market ain't gonna work. Changing the culture and people's perceptions of women will, but changing culture doesn't happen overnight.
Thanks to my beautiful and lovely wife for the story link.