A man can not be with a marriageable woman in seclusion. This is khalwah and is prohibited. Ibn A'bbaas reported that the Prophet (saw) said "None of you should be alone with a woman unless she is with a mahram" (BUKHAARI, MUSLIM) Note some people think that if you are alone with two women then this is allowed because the hadeeth prohibits being with one woman.

This is broken reasoning and weak extraction from the text and an ignorance of the general rules relating to the Islamic system governing the movements of women in the society with regards to men whom can be married.

Firstly this text prohibits khalwah, that is seclusion between a man and a woman. As for the evidences relating to the free mixing of the sexes then they are numerous in the Quran and sunnah and prove that generally this is not allowed. As for this hadeeth, it did not say that "....do not be alone with a woman unless another woman is present" rather it said ".....unless she is with a mahram"....... This indicates the disapproval of the mixing of the sexes. When we look to the texts we see that this is because the shari'ah cuts off the harms of unlawful sex and that which leads to it and that which is associated with it. Jaabir reported that Rasool Allah (saw) said “A man must not spend the night in the house of a woman unless he is her husband or a mahram” (MUSLIM, Bulooghul Maraam [no.960 p.396])

A'bdullah ibn U'mar reported that Rasool Allah (saw) said "A woman is one to be kept indoors. Surely when she emerges from her house the devil eyes her and it is certain that a woman is nearest to Allah when she is inside her home" (TABARAANI in Mu'jam al Awsaat) and U'mar reported that the Prophet (saw) said "When a man is alone with a woman then the third with them is Shaytaan" (TIRMIDHI) and it is reported that the Messenger (saw) said "The glance is a poisoned arrow of Shaytaan. Whoever lowers his gaze for Allah, He will bestow upon him a refreshing sweetness which he will find in his heart on the day that he meets Him" (TABARAANI, AL HAAKIM, AHMAD)

Allah (swt) says "And tell the believing men to lower their gaze and protect their private parts. That is purer for them. Verily Allah is All Aware of what they do" (an Noor 24:30) and Jareer ibn A’bdullah reported “I asked Nabi (saw) about the glance at a non-related woman and he (saw) commanded me turn away my glance” (ABU DAWOOD) So these evidences prove the prohibition of socialising with the opposite sex as they prohibit what is less than that. If we are allowed to unrelated men and women are allowed to speak with each other and entertain each other and mix freely then what is the meaning of prohibiting a glance at them?

Abu Hurayrah reported that Nabi (saw) said ".....The eye does zinaa by the looking, and the ears do zinaa by the listening, and the zinaa of the tongue is to talk and the adultery of the hand is to touch and the zinaa of the legs is to go to (the forbidden place) and the heart desires and the private parts confirm or contradict that" (BUKHAARI, MUSLIM)

So this proves there is the prohibited speech, listening, touching and mixing withj regards to women. And this is when the mixing is just socialising and for jaahil motives etc.

However there are situations and reasons which make social contact between them permissable, but this is not allowing khalwah [seclusion] some examples are:-

1) Trading
2) Medical need
3) Da'wah
4) Commanding ma'roof and forbidding munkar
5) Studying the deen
6) The education which is of the nature of fard kifaayah e.g. Arabic language, administration, science etc.
7) Fulfilling the needs e.g. to ask someone for directions to aquire your needs and rights
8) Proposal of marriage
9) To convey the Islamic greetings

There are also other reasons and Allah knows best. However, the general ways of socializing with women, free mixing and flirtation is not from the Islamic way of organising society. However some have also gone to extremes in these affairs and have fabricated a rigid situation that did not exist in the time of the prophet (saw) and in the period of the first three generations, and this must be avoided as it can make society unworkable, Islam actually gives us the best laws and methods and we should not add to them nor should we take away from them.