The present invention relates to a client terminal and an operation method of a client terminal, a transmission server and an operation method of a transmission server, and a program, whereby manufacturing costs, developing costs, and maintenance costs can be reduced for a television receiver which is a client terminal, regarding a configuration for distribution of contents from multiple service providers.An application (program) 111 capable of operating on a browser 91 presents VoD contents which it can select itself, based on control information, and requests a VoD server 72 for distribution of VoD contents selected out of the presented VoD contents via a first network which is a bi-directional IP network. In response, a headend 12 which is a transmission server supplies to a client terminal 13 via a second network of which downstream transmission band has sufficient band for transmission of contents. The present technology can be applied to an IPTV distribution system.