frontline
adjective [ before noun ]
HR, WORKPLACE (also front-line) uk/ˈfrʌntlaɪn/ usused to describe an employee who deals directly with customers, or who is directly involved in making a product:
A positive interaction with a client can give a frontline worker great satisfaction.
used to describe a manager whose job involves dealing directly with a group of employees:
Good workload management depends on the efficiency of the frontline manager.