The present technology relates to a coding device and method, and a decoding device and method, and a program capable of reducing the amount of calculations for decoding.A separating unit separates a supplied bit stream into coded data of channel sources including a dialog source, coded data of additional data sources, and coded data of dialog information. A dialog information decoding unit decodes the coded data of the dialog information. When the dialog information acquired by the decoding is presented to a viewer, the viewer selects one source from the dialog source and some additional dialog sources. An additional dialog source decoding unit decodes only the coded data of an additional dialog source selected by the viewer. An additional dialog selection unit outputs a viewer-selected audio signal from among the audio signals of the dialog source and additional dialog sources in response to the selection instruction of the viewer. The present technology is applicable to coding devices and decoding devices.