Sheryl Sandberg of Facebook, Marissa Mayer of Yahoo and Angela Ahrendts of Apple have high-profile positions at tech companies, but they are the exception, not the rule.Credits: World Economic Forum/Magnus Hij/Reuters

Institutionalized sexism is a subtle beast, a pervasive creature that exists in multiple forms across society. When it comes to the lack of women in technology, we must eradicate this animal in order to ensure that the industry is truly representative of the planet it is changing.

That's not to say there are no women in technology -- there are, but any social scientist will tell you the true nature of institutionalized prejudice is well masked by the existence of a few high-profile members of the group. The existence of a few successes doesn't mean barriers don't exist. Facebook COO Sheryl Sandberg and Yahoo CEO Marissa Mayer may be women in senior positions within the technology industry, but they are the exceptions rather than the rule.

You only need to take a look at this report on The Atlantic website to get a sense of what women need to fight against:

* The fast-growing tech industry generates far more new businesses, industries and jobs than any other sector.

* Tech-sector jobs are much better paid than the average.

* Yet there are more vacancies within the sector than people to fill them.

* Despite this, research by Maria Klaw at Harvey Mudd College shows young women don't think technology is interesting.

* That research also reveals a perception among young women that they wouldn't be good in a tech-sector role.

* It also tells us they "wouldn't feel comfortable" with the people they would work with.

In combination, these and other challenges explain why just 0.4% of female college freshmen say they intend to major in computer science and the number of females studying the subject has halved since 1985.

That's ridiculous. We're talking about a lively industry that touches almost every part of human experience, that rewards its workers with above-average salaries, and that has jobs going begging. We need women to help shape a better and more diverse future.

Why aren't more women involved? Despite accounting for 47% of the U.S. workforce, women hold only 25% of jobs in computing. Worse, just 20% of Fortune 500 CIOs are women -- and even then, the relative lack of media attention given to these women makes it almost forgivable to imagine the only women in technology are Sandberg and Mayer. Which isn't true.

That's the point. There are multiple levels at which institutionalized sexism can be seen at work within this situation:

Strike one

Women's technology success stories are insufficiently reported by the media and within education. In more general terms, just 3% of U.S. educational materials focus on female contributions across history. Young girls are not being given access to positive historical female role models that could serve to inspire them to play a part. And when they look to the media for stories of strong women, they are unlikely to see many mentions of women in tech.

The truth is that women excel in the sciences. A STEM report claims: "In the United Kingdom, girls are shown to outperform boys in subjects including Science, Technology, Engineering, and Mathematics."

The lack of female interest in these fields is nothing to do with talent or ability.

Strike two

There's been huge debate across the education sector in both the U.S. and U.K. as pedagogues ask why women aren't more interested in topics such as physics. Some argue this traditional gender divide has led syllabus creators to manufacture curricula that appeal to the group most interested in the topic, boys. This perpetuates the divide.

Yet a new study by University of Texas sociologist Catherine Riegle-Crumb in the journal Social Science Quarterly shows that this divide fluctuates: "In communities that had a higher percentage of women in the labor force who are working in science, technology, engineering and math, ... girls were as likely as boys to take physics, or even more likely," the report explains.

The lack of female role models in the field has to be the reason females are not pursuing careers in these fields: after all, we know women excel in these subjects. In the absence of national or local role models, girls are less interested in the topic. No one has overtly decided this should be the case; it's just the nature of institutionalized sexism.

Strike three

Those females who do somehow make it into the technology industry must then compete with the legendary glass ceiling. Be honest: How many of us have seen relatively weak male employees promoted while incredibly talented females get ignored?

You can deny the existence of this glass ceiling if you wish, but then ask yourself why the U.S. Senate is only now expanding a bathroom for women? And there was no bathroom for women at all as recently as 25 years ago. Is there any example of institutionalized sexism more damning than that?

More evidence of the glass ceiling: 47% of the labor force is made up of women, but just 20% of the top jobs in the Fortune 500 are filled by females.

The existence of this bias is also hinted at within the statistic that in 2010, "the median weekly earnings of women who were full-time wage and salary workers were $669, or 81% of men's $824."

The inconvenient truth seems to be that women such as Sandberg and Mayer are an exception, rather than a rule.

What can we do?

Improvement of the position of women within the technology industry will require positive actions such as:

* Providing young people with good female role models on a local, national and international basis.

* Ensuring that the curriculum for computing and science education is extended to include such role models within class.

* Taking steps, within technology companies, that ensure that hiring and promotion decisions are based on talent and ability. ( Cisco is a good example of a company doing something to address this).

* Sharing experiences. Women in senior roles within technology could help by volunteering to tell their stories at local colleges and schools in order to enhance perception of good role models (I'm looking at you, Angela Ahrendts and Andrea Jung.)

These few steps won't solve the situation overnight and will need to be taken in conjunction with other actions on a local, national and international level. They will help, but I don't expect things to change overnight. In fact, I believe the position of women in the tech industry won't fundamentally change for at least one generation subsequent to these and other measures being put in place.

These steps should already have been taken. We are wasting talent, squandering ability and damning diversity within an industry that's becoming so pervasive it now dominates almost every part of life.

This has to change.

Jonny Evans is an independent journalist/blogger who first got online in 1993. He's author of Computerworld's AppleHolic blog and also writes for others in the U.S., the U.K. and Europe. Winner of an Azbee Award in 2010, Jonny enjoys new and disruptive technology and likes music almost as much as he likes his large and shiny dog.

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