The Ruling on a Woman Working in a Place Where There is Mixing of the Sexes

Question :

Is it permissible for a young woman to work where there is mixing with men, bearing in mind that there are women other than her in the same place?

Answer:

It is my opinion that it is not permissible for men and women to mix in places of government employment, places of private employment, or government or private schools. This is because mixing results in much corruption, even if it be only the loss of modesty in the women and the loss of respect from the men. When men and women mix, men lose their respect for women and the women act immodestly before them. And this (I mean mixing between men and women) is opposed to what is necessitated by the Islamic Law and is opposed to what the righteous Salaf used to follow. Do you not know that the Prophet designated a special place for the women when they went out to perform. he 'Eid prayer, so that they did not mix with the men, as it is reported in the authentic Hadith? (It is reported) that when the Prophet addressed the men, he descended and went to the women and warned them (against sin) and reminded them (of Allah) and this proves that they could not hear the sermon of the Prophet, or that they heard it, but did not comprehend what they heard from the Messenger of Allah. Also, do you not know that the Prophet said:

"The best rows for the women are those in the rear and the worst of them are those in the front, while the best rows for men are those in the front and the worst are those in the rear."

It is only due to the nearness of the first rows of the women to the men that they are the worst of rows and it is because the last rows put the women further away from the men, that are the best rows. And if this is the case in communal worship, then what of situations other than worship, when it is known that when a person is engaged in worship, he is as far as he can be from sexual desire? So how will it be if the mixing takes place in situations other than worship and Satan reaches every part of the human body as blood reaches it? Then it is not unlikely that temptation and great evil will arise during this mixing. So I call upon our brothers to abstain from mixing and to realize that it is one of the most dangerous things for men, as the Messenger said:
"I have left behind me no greater trial and temptation (Fitnah) to men than women."

And we, all praise and thanks be to Allah we, the Muslims-have a particular distinction over others by which we must distinguish ourselves, and we must praise and thank Allah, Most. Glorified, Most High that He has favored us with it. We must know that we should follow the Law of Allah, the Most Wise, Who knows what is right for the creatures and their countries, and we must know that those who flee from the Path of Allah, the Almighty, the All-Powerful and from the Legislation of Allah, they are astray and their way will lead to corruption. This is why we hear that those communities whose men and women used to mix freely are now trying their best to rid themselves of this, but how can they expect to return to their original state from such a distant place? We ask Allah, Most High to protect our country and the Muslim countries from every iniquity, evil and trial.

Source:
Ibn 'Uthaimin
Fatawa Islamiyah, Vol. 5 Pages 144-145-146