The first 90 days give a new marketing operations leader, or a newly reorganized team, a critical window to build trust, understand the organization, and set a clear strategic direction. During this time, leaders assess capabilities, align with executive priorities, and forge cross-functional partnerships. Success depends on identifying quick wins, generating momentum, and balancing immediate execution with long-term vision. This guide outlines a 90-day roadmap to help marketing operations leaders deliver early impact and lay the foundation for sustained success.