According to a famous Talmudic story (Babylonian Talmud, Tractate Shabbat: 31a), a gentile once approached Rabbi Hillel and asked to be taught the entire Torah while standing on one foot. Hillel replied, 'Love your neighbour as yourself. That is the entire Torah. The rest is simply an explanation. Go and learn it!' In much the same way, Jewish law can be described in one word-Torah. All the rest is simply an explanation. The Torah, also known as the Bible, the five books of Moses, and the Pentateuch, was written over 3,000 years ago. Since then, Jewish law has developed various interpretations and applications of the Torah, interpretations of those interpre- tions, and so on. Jewish law contains civil dictates as well as religious protocol. Problems that arose in the framework of religious life and problems surrounding civil relationships both found solutions in the same legal source-the Torah and the Halacha, the Jewish legal interpretations and rulings. This chapter on water law in the Jewish tradition provides insight into Jewish law and custom in general, and rules related to the protection of water sources in particular.One should not look, however, to find a written code of Jewish law, as there is none.