The exercise of defining a relevant market is often an important component of the CRTC‟s deliberations on an issue, including the CRTC‟s role in reviewing proposed mergers and acquisitions, the regulation of wholesale markets (although, the CRTC has become much less active in terms of direct regulation in recent years), and, the CRTC‟s role in promoting the production and availability of Canadian [...] The core objective, and so the core tools, of determining the boundaries of a market – to help identify market power, that is, the ability of a firm or a group of firms to profitably maintain prices above the competitive level for a non- transitory period of time – remain relevant. [...] The remainder of the report is structured as follows: Section 2 provides a high-level overview of the regulatory framework for the Canadian broadcasting sector and addresses the question of why market definition issues are important to the Commission in carrying out its mandate in the new digital environment, particularly in regard to audio and audio-visual products. [...] To maximize the advertising value of the Canadian broadcasting rights to such programming and thereby, it is hoped, maximize the dollars that are available for the production of Canadian programming, the Commission requires broadcasting distributors to substitute the Canadian signal for the American signal when the same program is being aired on both stations so that viewers will see only the adve [...] The objective of determining the boundaries of a market is to help identify market power; that is, the ability of a firm or a group of firms to profitably maintain prices above the competitive level for a non-transitory period of time.