Safe and effective methods of preconception gender selection through flow cytometric separation of X- and Y-bearing sperm could greatly increase the use of gender selection by couples contemplating reproduction. Such a development raises ethical, legal, and social issues about the impact of such practices on offspring, on sex ratio imbalances, and on sexism and the status of women. This paper analyzes the competing interests in preconception gender selection, and concludes that its use to increase gender variety in a family, and (...) possibly for selecting the gender of firstborn, might in many instances be ethically acceptable. (shrink)