A human resource of a company or organization is generally an employee, and the department that communicates with employees and manages employee-related issues—including job applications, job interviews, drug tests, employment offers, wages, benefits, paid time off (PTO), unpaid leave, employee reviews, termination of employment, and unemployment insurance claims—is often known as the human resources department, or human resources, or simply HR. An employer’s human resources department may consist of one person in a smaller organization or many persons in a larger organization, and is often headed by a human resources manager or human resources director.

In Arizona, as in other states, the human resources (HR) department plays a critical role in managing the employer-employee relationship. This includes overseeing the hiring process, from job postings and interviews to drug testing and extending employment offers. HR is also responsible for managing wages, benefits, and paid time off (PTO), as well as handling unpaid leave in accordance with the Family and Medical Leave Act (FMLA) and other relevant state laws. Employee performance reviews and the termination process, including compliance with the Worker Adjustment and Retraining Notification (WARN) Act for layoffs, are also under the purview of HR. Additionally, HR departments in Arizona must ensure compliance with state-specific employment laws, such as the Arizona Civil Rights Act, and manage unemployment insurance claims in line with the Arizona Department of Economic Security's guidelines. The size and structure of an HR department can vary greatly depending on the size of the organization, with smaller companies sometimes having only one person responsible for HR functions, while larger organizations may have a dedicated team led by an HR manager or director.