I-O psychologists use their training and knowledge of psychological principles in a wide variety of settings. For instance, psychometrics and statistics are used in selecting/hiring employees; learning principles are used in training and motivation; and numerous social psychological concepts come into play when I-O psychologists work in the areas of leadership and job satisfaction.

Although I-O psychologists are not lawyers, they often provide consultation to employers in legal matters. Hiring, salary, and promotion practices must follow legal guidelines from the Civil Rights Act, the Americans with Disabilities Act, and other legislation. I-O psychologists are now becoming more involved in issues of sexual harassment, providing training to help avoid cases and consulting with management once an incident has occurred.