List and define the three major types of vertical marketing systems.

A vertical marketing system is a professionally managed and centrally coordinated marketing channel designed to achieve channel economies and maximum marketing impact. There are three major types of vertical marketing systems: corporate, contractual, and administered. Corporate vertical marketing systems combine successive stages of production and distribution under a single ownership, either through forward or backward integration. Forward integration is when a producer owns an intermediary at the next level in the marketing channel. Backward integration is when a retailer owns a manufacturing operation. Contractual vertical marketing systems consist of independent production and distribution firms that integrate their efforts on a contractual basis to obtain greater functional economies and marketing impact than they could achieve alone. Administered vertical marketing systems achieve coordination at successive stages of production and distribution by the size and influence of one channel member rather than through ownership.