From cave days to present, human resources have been integral parts of business. For a long time, however, business owners and managers viewed workers as resources that are not much different from spare tires, mules, and wagons. They were replaceable, expendable, and could run on indefinitely should there be need for them to do so. This view resulted in deplorable working conditions ranging from discrimination and harassment to underpayment or nonpayment of wages and lack of proper workplace safety and sanitation. It took a long time for the modern concept of human resources to sink in. It was not until the 1920s when employment experts and psychologists gradually redefined the way companies view workers - from being interchangeable parts to unique individuals specially equipped to do highly specialized tasks. By the 20th century, companies finally recognized the importance of human resources. The new goal is not to exact as much labor from the human capital but to maximize its return on investment without putting lives, principles, or ethics in jeopardy. The articles herein are all about human resources.