The document defines key aspects of defining business structure and infrastructure in CA Service Desk Management (CA SDM). It discusses setting up sites, locations, organizations, and contacts to represent the business structure. It also covers defining configuration item families and classes, manufacturers, models, service statuses, vendors, and vendor types to represent the business infrastructure. Finally, it discusses multi-site support which allows data sharing between multiple CA SDM installations while maintaining separate business rules, and multi-tenancy which allows multiple independent tenants to share a single CA SDM implementation.