Insha Allah this question reaches you in the best of health, Imaan, and Taqwa. I am in High School and am doing a "Women in Islam" presentation for my class. In my presentation I am talking about the most sensitive topics about women in Islam because I want them to know about it now so in the future when someone mentions it to them they will be able to tell them about it. I also hope that my presentation will clarify any misunderstandings that Islam oppresses women. As one part of my presentation I discuss polygamy, which is very difficult to talk about to them. Should the husband ask his 1st wife first if he could marry a 2nd, 3rd or 4th wife? Does the first wife have to agree and give him the "okay" before he marries another? Or does she just have to know about it without agreeing?
Jazaka Allahu Khairen for your time. I truly appreciate it. May Allah reward you in this life and the hereafter for all you have done for the Muslims through this web site. Ameen.

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

The husband is not obliged to take the opinion of his first wife before marrying the second one and her consent or knowledge are not pre-conditions to such a marriage.

For more benefit that a husband does not need the permission of his first wife to take a second wife, please refer to Fatawa 121947, 82988, 82068 and 84411.

Allah knows best.