An Autonomous Concurrency Management (ACM) subsystem enables test instruments (operating as servers) to reliably and efficiently handle a variety of seamless multi-device-under-test (multi-DUT) scenarios and with minimal cooperation from the original equipment manufacturer (OEM) client software (e.g. test plans, hardware abstraction layer, etc.). Concurrency capability is built directly into the test instruments. Making the instrument based concurrency autonomous means the OEM software code base need not be specifically implemented for concurrency, potentially saving thousands of lines of OEM software code. To support basic concurrency scenarios where clients asynchronously share the instrument, as well as advanced concurrency scenarios such as a broadcast scenario, the ACM includes software lock, client separator, client rendezvous, and client observer functionality. An instrument ACM subsystem simplifies the problem from the client's perspective by moving the complexity to the lowest software layer, the RF (test) instrument.