Leather industry is one of the key economic drivers, creating million of jobs and generating significant foreign exchange but this industry also faces environmental challenges. Many industries are known for the release of hazardous waste but tanneries are notorious for releasing slow poisonous substances to the biosphere and undermining the quality life of humans, plants and animals. Tanneries use significant amount of chromium salts during tanning operation, which leads to unwanted release of large quantities of effluents and solid waste, i.e., sludge, containing chromium derivatives. These contaminants ruin the ecological balance and survival of various life forms. This chapter delves into the physical characteristics of tannery effluents, focusing on liquid and solid waste streams. It identifies main pollutants such as sulfides, ammonium salts, chlorides, biological oxygen demand (BOD), and heavy metals. Impacts of the assorted tanning processes on effluent composition is also described. Solid waste, primarily in the form of sludge, unveils additional environmental challenges due to heavy metal contamination, particularly in developing countries such as Pakistan, where inadequate waste management practices are prevalent. This chapter explores the detailed environmental impact of tanning practices including water contamination, soil degradation and air emissions. Considering the long-term consequences of inadequate waste disposal in tanneries highlights need for eco-friendly tanning approach and opportunities for sludge valorisations. Conventional tanning practices include chrome-based tanning which are effective but exhibits irreversible results. This review addresses the setbacks in current practices and explores emerging and innovative eco-friendly alternatives such as chrome-free tanning, waterless tanning, enzymatic tanning and nanotechnology that use non-hazardous steps. Moreover, this chapter discusses the treatment of tannery wastewater and the potential integration of treated wastewater reuse to reduce freshwater consumption in water-scarce regions of world and environmental impacts. Tannery waste water treatment includes reverse osmosis (RO), nanofiltration (NF) and ultrafiltration (UF) also hybrid treatment technique that comply many physical, chemical and biological techniques found more effective and producible. Conclusively, this study emphasizes the urgent call for the authorities and leather industry to adopt sustainable and retained regulatory measures for improved waste management, technological innovation and stricter environmental regulations to ensure the life safety and protection of environment.