Abstract: There is disclosed an expandable multiline dialing controller which is connected to a computer hosting a database of telephone contact records. The controller is rendered expandable by a capacity expansion interface which allows the connection of second or subsequent dialing controllers in a chain, all of the dialing controllers in the chain sharing the connection to the single computer in telephone contact database. Available operators and available outside lines could be shared between the dialing controllers in the chain. A multiline dialing control system comprising a plurality of such dialing controllers is also disclosed. Also disclosed is the method of conducting a telephone contact campaign in such an expandable hardware environment.