Own a mid-market B2B SaaS customer portfolio from onboarding through adoption, renewal, and expansion. Lead executive business reviews, demonstrate ROI, map customer workflows, identify churn risks and expansion opportunities, negotiate renewals, and maintain accurate health and forecast data. Partner with Professional Services, Support, Sales, Product, and Engineering while contributing to customer success playbooks and health-scoring models. The role requires a proactive, commercially confident approach and familiarity with professional-services operations, including utilization, billable hours, and project margins.