The effect of human resources in an organisation?

This department has come a long way from the "Personnel Department." A lot of it has to due with court cases and the realization that HR has a place in a company to educate its workforce, benefits, compliance, etc.

By having an HR department, they are able to make sure employees are acting appropriately in the workforce (in relation to sexual harassment or violence), hire/fire appropriately (without causing litigation or an adverse effect on employee selection), take care of benefits (enrolling employees, choosing benefits that will aid employees health-mental/physical), training the workforce, helping managers track employees career performance, and even the presence of someone to talk to is still important for an employee's voice to be heard. This all builds the companies workforce in helping retain people, attractive new talent, and motivate employees to work on the company's mission and goals.

In my own experience, I have seen companies that have not had an HR Department (mostly because of pure size) and it usually results in chaos and missing regulation deadlines. However, I have also seen very ineffective HR Department that do not have the knowledge or drive to embrace all functions of HR. It will depend majorly on the type of people in this department and how the higher ups respect their opinions and presence in the board room.