This chapter provides a comprehensive overview of wastewater sludge management. It coveres composition of sludge, its treatment objectives, processing methods, and strategies for disposal and resource recovery. Sludge contains up to 99.5% water along with organic matter, nutrients, and potential contaminants. Based on source from wastewater treatment plant, it is classified into primary, secondary, mixed, and digested types. Treatment aims to reduce volume, stabilize organic matter, destroy pathogens, recover resources, and ensure regulatory compliance. Key methods include preliminary operations, thickening, stabilization, conditioning, dewatering, and drying. Pretreatment technologiee which can be employed are thermal, ultrasonic, and emerging methods enhance biodegradability, dewaterability, and energy yield. Disposal and reuse options range from landfilling and incineration, use in construction materials, fertilizers, and energy recovery through processes like pyrolysis, gasification, and anaerobic digestion. The chapter highlights a shift toward circular economy approaches, integrating sustainable practices to convert sludge from a waste into a valuable resource.