This study reviewed sustainability practices of firms in the emerging markets as aligning with the recent development of sustainability practices and reporting is crucial for the firms. Content analysis was used to quantify the practices of sustainability (environmentally, economically, socially, and governance-wise) of listed deposit money banks in Nigeria against the GRI sustainability guidelines. From the trend analysis and descriptive statistics carried out the study found that the practice of sustainability by these firms had been dwindling ranging from non-compliance to full compliance with the GRI requirements. Thus, the study recommends that the policy makers and regulators in the emerging nations should intensify efforts to encourage the continuous compliance of these firms with sustainability requirements.