In our very varied business world, which includes both sexes, is it ever permissible for a man to shake the hand of a woman?

Shaking hands with women who are not close family is not permissible in Islam. However, in cases where refusal to shake hands would result in embarrassment or disrespect, it does become permissible, provided it is not done with any bad intent. It is worth mentioning that the Sunni schools of thought consider shaking hands with members of the opposite sex nullifies wudu. They base this on their understanding of Qur’an 4:43 and Qur’an 5:6. However, these two ayat have no relevance to shaking hands. According to Imamiyyah understanding, they refer specifically to sexual intercourse.