Fourth-party logistics (4PL) companies are defined as providers of comprehensive logistics services that manage and control the entire supply chain process for their clients. 4PLs provide a wide range of services, from strategic planning and design to execution and control. They are responsible for managing the entire supply chain, from the supplier to the customer, and can provide a variety of services such as inventory management, order fulfillment, transportation, warehousing, and reverse logistics. 4PLs also have the capability to integrate and manage multiple third-party logistics (3PL) providers to create a comprehensive supply chain solution. 4PLs provide an invaluable service to their clients by providing a single point of contact for all supply chain activities, allowing them to focus on their core business. By leveraging their expertise and resources, 4PLs are able to create a cost-effective and efficient supply chain solution that meets the needs of their clients.