Copyright can be a challenging maze for library folk and educators, and no area causes more stress than the Fair-Use Doctrine. This is mainly because it deals with gray areas of use, presenting guidelines rather than rules.
The Common Sense of the Fair-Use Doctrine is a brief essay in the current Chronicle of Higher Education that is meant to both inform and empower those who would benefit from the fair use of copyrighted works:
Twenty-five years ago, fair use was widespread and uncontroversial. Journalists, scholars, and documentarians employed it regularly. Publishers and other distributors routinely issued works rich with fair-use claims. But increasingly over the last two decades, that has changed, as large media and software companies have fought for greater copyright protections and ramped up their public-relations campaigns and legal actions.
A good starting point for further research is Wikipedia’s Fair use entry.
link found via Stephanie L. Gross