Case Study: Marsh McLennan retains critical software knowledge and accelerates onboarding with CAST Imaging

Marsh McLennan preserves critical software knowledge and boosts the speed of delivery

Marsh McLennan, a global professional services firm with 83,000 employees and a technology organization spanning 60+ countries, manages a portfolio of more than 3,000 applications—including 800 custom apps totaling over 100 million lines of code. As the company consolidated into a unified technology shared-service model, it needed to transfer deep application knowledge quickly, reduce dependence on individual SMEs, and maintain or improve service levels during rapid transitions.

Marsh McLennan launched an Insights program using CAST Imaging to automatically extract application structure and relationships into a living, Google‑map‑style knowledge base. The interactive architecture blueprints made tacit knowledge explicit, accelerated onboarding, shortened the learning curve, and boosted team agility—reducing SME dependence, improving decision‑making, and surfacing previously hidden insights about application internals.

Marsh McLennan

Alan Capper

Global Leader of App Modernization