The berachah of Al Netilat Yaddayim

Hi,

Ordinarily, we recite a berachah before performing a mitzvah (עובר לעשייתן). However, one who has not yet washed his hands may well have dirty hands, and in such a circumstance one should not recite a berachah.

Therefore, our practice is to recite the berachah after washing, but before drying our hands. Since drying one's hands is considered part of the mitzvah, it is still somewhat 'before' performance of the mitzvah.

(Shulchan Aruch Orach Chaim 158:11-12; Mishneh Berurah 158:40-42)

Have a great day,
Mordechai