Departmentalization involves grouping jobs and activities into departments to achieve organizational objectives. There are three main types of departmentalization: functional, territorial, and customer-based. Functional departmentalization groups employees based on their specialized function, such as marketing, finance, or production. Territorial departmentalization groups employees based on geographic region. Customer-based departmentalization creates departments oriented around different customer markets or channels. The document discusses the advantages and disadvantages of each type and when each would be most suitable depending on factors like company size and activities.