According to many authorities, the reading of the Parasha of Zachor, "Remember what 'Amaleq did unto you", is an obligation from the Torah (as opposed to from the Rabbis). So every man must ensure that he finds a Minyan where it will be read.
There is an opinion that women are obligated to hear the reading also, and this is the custom followed by most Ashkenazim. Sephardim follow the opinion that women are not obligated to hear the reading, even though they have an obligation to "remember". If a woman does come to hear it, she should have in mind that she is not taking it upon herself as a Neder (vow), so that she will not obligate herself to hear it the following years.
If she does hear the reading, however, she will get a reward for doing so, as one does in every case where one is not obligated to perform a commandment but still does.
(See Sh. 'A. 685:7. Kaf Hahayim, ibid, 30. M.M. Hilkhoth Haggim 62: 12, Torah Lishmah 187))
