Reuven Hammer is a rabbi and author, affiliated with the Masorti movement in the United Kingdom and in the State of Israel. The Masorti movement is a part of Conservative Judaism.
In the UK he served as an interim rabbi in the New London Synagogue from October 2005 until July 2007.
He is a former President of the Rabbinical Assembly. He is one of the founders of the Masorti Movement in Israel. He is the head of the Massorti rabbinic council, the Va'ad Halakhah. The Ziegler School of Rabbinic Studies of the University of Judaism (now the American Jewish University) awarded him the Simon Greenberg Award for Lifetime Achievement in the Rabbinate, in 2003.
In 2003 the Jewish newspaper The Forward named him as one of the “Forward 50."
Or Hadash: A Commentary on Siddur Sim Shalom for Shabbat and Festivals, 2003. It contains the complete text of Siddur Sim Shalom for Shabbat (the Jewish Sabbath) and festivals, surrounded by a comprehensive commentary. The page layout loosely resembles that of the Talmud.
Or Hadash: A Commentary on Siddur Sim Shalom for Weekdays, 2008. It contains the complete text of Siddur Sim Shalom for weekdays, surrounded by a comprehensive commentary.