From gender-based pay gaps to leadership roles, advancement opportunity to corporate culture, the treatment of women in the workplace – and how to enhance growth opportunities for women executives – is and has been under continual focus.But now this focus is frequently combined with a new, and growing trend: The aging and multigenerational workforce. The numbers may surprise you: The number one growing demographic in today’s workplace is women over 55. In fact, the number of people over 55 is going to be 25% of our workforce in five years.The statistics come from Diane Flynn, Co-Founder and CEO of ReBoot Accel, accelerating the careers of women in the workplace and consulting with high-growth and Fortune 500 companies, as she puts it, “interested in creating workplaces where women thrive.”It’s also why – with companies like Airbnb, Udemy, Visa and Gap, Flynn has launched The Silicon Valley Longevity Project, which seeks to bring together companies recognizing that “How companies prepare for and respond to changing workplace demographics will have a profound influence on their ability to compete in the global marketplace and will affect the communities in which they operate.”More background: Flynn previously served as Chief Marketing Officer of GSVlabs, a marketing executive at Electronic Arts, and an associate consultant at The Boston Consulting Group. Like many professional women, she also left the workforce for a period to raise her family.So what can and should companies do? And what lessons can be learned from executives and firms who have succeeded – and from those who have failed?