ICICI Bank implemented a CRM solution in phases to create a single customer view and better understand customers. The first phase created a data warehouse integrating 6 systems. The second phase expanded data and added segmentation tools. Future phases aim to automate campaigns and integrate additional systems. Key challenges included lack of models, disparate systems, and building a data-driven culture. Critical success factors were a technology focus, independent CRM team, and phased approach. Benefits included increased revenues, cost savings, and improved decisions. The roadmap includes advanced analytics, automated campaigns, and customer profitability models.