First ladies' key role in presidential libraries

First ladies' key role in presidential libraries

In just over a century and a half, the concept of a presidential library has evolved from a small room in a home where first lady Sarah Polk kept her late husband's letters and mementos into multimillion-dollar complexes that house thousands of official records from the presidents' years in office.

But presidential libraries are no longer just a means of preserving the legacy of the men who have occupied the Oval Office. Modern-day libraries are designed to highlight the partnership between the president and first lady. And increasingly, it is the first lady who leads the charge in making sure her husband's vision for his library comes to fruition.

As the Barack Obama...