A COM/COM+ developer designs and implements software components using Microsoft's Component Object Model (COM) and COM+ technologies. They create reusable objects to integrate applications and enable communication between software modules. They work on system-level programming, handle memory management, concurrency, and error handling, while ensuring security and transaction integrity. They also maintain and debug existing COM/COM+ applications, provide technical support, and document system specifications. They work closely with other developers to ensure that components work together seamlessly. Their work is crucial in creating scalable and efficient distributed applications on Windows platforms.