Shimon D. Eider (December 2, 1938 - September 28, 2007) was an Orthodox rabbi and a posek (decisor of Jewish law).
[1] R. Eider, a graduate of Yeshiva University High School for Boys, was a pioneer in the field of Jewish law in English.
He was a longtime resident of Lakewood Township, New Jersey and an esteemed member of the advanced Kollel of Beth Medrash Govoha where he was a student of Rabbi Aharon Kotler.
Eider frequently consulted with major rabbinic authorities in the writing of his books, as seen from the countless footnotes.
His style of writing is the foundation of most English works of Halacha published today.