Recent decades have seen a surge in corporate sustainability reports (SRs); their proliferation, however, does not ensure effective and consistent reporting on materiality. To improve the completeness, consistency and uniformity of SRs, this study aims at providing a review on the definition and identification of materiality and to propose screening methods for materiality assessments using publicly available resources. We found that most acknowledged standards and initiatives diverge in their definitions and approaches towards materiality. Four screening methods are proposed, including two that are directly usable: (1) Sustainability Accounting Standards Board Materiality Map™ and (2) Global Reporting Initiative (GRI) Sustainability Topics for Sectors; and two involving more desktop research: (3) GRI’s Sustainability Disclosure Database and (4) modeling from a life-cycle perspective. The second and third approaches are tested through a comparison study for the apparel and energy industries in selected regions using content analysis. The results indicate that the two approaches, with different levels of complexity, yield inconsistency in obtaining the most (i.e., the top three) material topics. The GRI’s Sustainability Disclosure Database is recommended for practitioners due to its balanced disclosure on management, economic, environmental and social sustainability themes.