eESI uses a detailed Customer Service Agreement to legally become the co-employer with our clients. This creates a strengthened relationship that involves and benefits all parties, eESI, your company and your employees. As your PEO, we become the employer of record to manage client’s needs in the areas of Human Resources (HR) | Risk Management | Employee Benefits | Payroll Administrative services. Your company retains direction and control with all daily activities and employees. And your employees have a complete HR resource for their employment, benefit and payroll needs.