Segment reporting has always been promoted as a mean to comprehend more adequately the activities and performance of the entire enterprise in order to make a better judgment about its future perspectives. It has been receiving attention from a variety of institutions, both at national and international levels (FASB, CICA, IASC/IASB, EEC, OECD…). For this, one of the early issues discussed by standards setters was the segmental reporting issue and all its relating questions. In response to user concerns regarding segment reporting, The American FASB jointly with the Canadian ICCA issued respectively SFAS No. 131 and ICCA 1701, Reporting Disaggregated Information about a Business Enterprise, in 1997. This standard became effective for fiscal years beginning on or after January 1, 1998. The move towards a new tailored standard was based on a segment defining approach called the approach. Under the management approach, a company would report financial information about each of its major organizational units for which financial results are already maintained and analyzed by top management. Accordingly, companies have to publish their segmented data by focusing on information that reflects the manner in which the entity manages its business activities and being used as a basis for their operational decisions making and used for their internal performance measurement. According to a considerable number of studies, the new standard enriched the informational environment by the production by a great volume of segment information disclosed by diversified companies. Moreover, these studies showed that the risk associated with the firm, the bid-ask spread, the information asymmetry and the dispersion among the financial analysts consensus all will be reduced following the adoption of this standard. In spite of the existence of this great support in favor of the virtues of this standard, there is also a growing of criticisms in connection with to it. In fact, considerable studies indicate that this disclosure standard is involved with the emergence of a number of issues. Most important among these is the proliferation of discretionary choices as regards segment disclosure on behalf of managers exerting as a result, an negative impact on the quality of the informational environment of the firm. Consequently, and given the advantages and the caveats of this standard, it is actually not clear if this standard will contribute to the existence of a lower or higher informational environment. The primary focus of this study is on how the governance variables interact with a mandatory disclosure requirement (SFAS 131, CICA 1701) in order to assess to scope for discretion allowed to managers through the segments identification process, profit and loss measurements, internal cost allocation and the use the provisions related to the application of this standard. Management have discretion in determining segments to be reported, identifying assets associated with each segment and in allocating shared costs across segments to calculate segment operating profit. This study examines corporate governance variables that may influence the chosen level of segment reporting. Association found between segment disclosure and governance may provide insight into segment reporting choices and should be of value in discovering additional aspects of the segment reporting requirements and in formulating future reporting policy. Therefore, it is hypothesized that segment reporting under the management approach offers a unique setting where it possible to study management discretion and accounting choices under a mandatory accounting regime.