Sexual discrimination is maltreatment or disparagement of one sex by the other, or of special preferential treatment given to one.
Allegations of Sexism against Men
"Women-only coaches" are becoming increasingly common in large cities in Japan, Brazil, and the Philippines. While proponents of these coaches say they are an effort to prevent rampant sexual harassment on trains , others believe that this segregation is an instance of sexism against men. Similar female-only accommodations are institutionalized in Muslim countries such as Saudi Arabia.
In Britain there are women-only library sessions, women-only swimming sessions in public swimming baths and women-only gyms. Feminists do not protest against any of these women-only spaces, but they have campaigned to remove men-only spaces such as gentlemen's clubs in London, and working men's clubs elsewhere in Britain. Feminists have also campaigned to allow women join sports clubs that were previously men-only such as golf clubs and golf tournaments (but not to allow men into the equivalent female-only clubs).
In some countries, if a rest room for women in department stores or movie houses etc. are full, a woman is allowed to use one for men. But not vice versa.
Some allege that affirmative action is sexism against men, because it gives advantages to equally or even less qualified women. They point to:
Norwegian Companies: The 500 companies listed on Norway's stock exchange face being shut down unless they install at least 40% women on their boards over the next two years. 
Russian Police set up Women-only Unit: Mikhail Tsukruk, the police chief in the southern Russian city of Volgograd, has set up the first women-only traffic police unit saying that 'research' [no details given] showed that women are less inclined to accept bribes. 
Some point to certain purported salary differences between men and women as evidence of sexism, particularly in the corporate world. Using the slogan "equal pay for equal work", agitators claim that many women in the same positions as men earn less. However, these allegations fail to accurately compare the actual work (i.e. value added to the company) done by the individuals in question. Since men and women naturally have different strengths and weaknesses, it's quite natural in certain jobs for men to perform better (and vice-versa - in certain activities women are better).
The fact that woman pursue family life and other non-monetary activities also contribute to a false sense of inequality when equity is determined by average earnings. Woman are often fulfilled and fully equal when performing their traditional duties within the home.
Atheism and sexism:
- 64% of Tokyo women stated that they had been groped in trains.