A Mainframe CICS Administrator is responsible for installing, upgrading, configuring, and maintaining IBM CICS Transaction Server environments to ensure high availability, performance, and security of enterprise mainframe applications. The role involves administering CICS infrastructure, supporting CICS web services, CICSplex System Manager, JVM Servers, and related vendor products, while monitoring system health and resolving production issues. The administrator collaborates with application, network, and infrastructure teams to troubleshoot complex technical problems, optimize system performance, implement changes, and ensure compliance with operational standards. Additionally, the role includes supporting disaster recovery activities, maintaining technical documentation, and providing 24×7 production support through rotational on-call and weekend schedules.