40 potential human rights impact has low probability but high severity, the former does not offset the latter. The severity of the impact, understood as its “scale, scope and irremediable character”, is paramount (see Guiding Principle 14). Equally, human rights risks cannot be the subject of a simple cost-benefit analysis, whereby the costs to the enterprise of preventing or mitigating an adverse impact on human rights are weighed against the costs to the enterprise of being held to account for that harm. As the commentary to Guiding Principle 18 explains, the process of assessing actual and potential adverse human rights impact typically includes “assessing the human rights context prior to a proposed business activity, where possible; identifying who may be affected; cataloguing the relevant human rights standards and issues; and projecting how the proposed activity and associated business relationships could have adverse human rights impacts on those identified”. An enterprise may choose to do self-standing assessments of its human rights impact or to integrate human rights considerations into its wider social and environmental impact assessments. It may be necessary to do a stand-alone assessment of human rights impact if the enterprise’s activities or operating context pose a heightened risk to human rights. A number of tools and methodologies for human rights impact assessments have been and will continue to be developed. However, as noted, this Principle does not aim at a single such assessment, but at an ongoing process of assessing impact that will draw on various sources. Besides the formal assessments initiated by the enterprise itself, other sources may contribute too. For example, a grievance mechanism through which affected stakeholders can raise concerns may provide indications of actual or potential human rights impact. News or expert reports on particular operating contexts or industry developments will likely be another source. Campaigns by nongovernmental organizations (NGOs) or other third parties may well be another. All these sources can feed into an ongoing process of assessing impact. When assessing their actual or potential human rights impact, companies should pay particular attention to marginalized or vulnerable groups. In some societies, inherent patterns of discrimination can be pervasive (but not necessarily apparent to outsiders). While companies are not responsible for such wider discriminatory practices, they should pay particular attention