Recently we've been having this dicussion in our (eclipse) community regarding diversity.
The scope of the discussion is not diversity with respect to gender, but rather the number of companies that provide committers to each project.
Another important factor to consider when trying to increase the number of women in open source is mentoring. For instance, the company I work for conducts day camps for middle-school girls to expose them to various aspects of computer science and engineering. We try to dispel the stereotypes of technology as a solitary, geeky discipline and expose them to the benefits of this career. Follow-up studies have shown that having this role model makes a significant difference in the career options these girls consider as they progess through their schooling.
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