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Abstract. Composting is a low-cost, scalable process to stabilize organic residues and create compost, a value-added product. While it has been implemented for a wide variety of manure types and digestates, composting lagoon sludge has been less explored. Lagoon sludge is a byproduct of swine operations in southeastern United States that can pose a management challenge to producers due to its high mineral and metal content. In this study, in-vessel aerated composting was carried out to evaluate the impacts of sludge inclusion rate, at 10% (LS recipe) and 20% (HS recipe) wet mass-basis, on process temperature, gaseous emissions, and end-product quality. Locally available, low-cost residues, including poultry litter, whole tree cuttings, coastal Bermuda hay and lagoon supernatant were used as recipe ingredients. During composting, maximum pile temperatures observed were 74°C (±2.7) and 74.9°C (±2.9) for the LS and HS recipes, both recipes met the time and temperature requirements for disinfection. The weight loss experienced by LS and HS mixtures was 34.5% (±0.5 %) and 34% (±0.1%) with 26.1% (±2.6%) and 27.8% (±2.8%) of organic matter loss respectively. The peak flux and cumulative emissions for CO2, CH4 and N2O are in the lower side of the range previously observed and can be potentially reduced further by using adsorbing agents and adaptive aeration methods. The study found that swine lagoon sludge is a viable feedstock for composting and that sludge inclusion at 20% (wet wt.) did not appear to inhibit microbial activity in either recipe or influence the process dynamics, i.e., weight, moisture, and organic matter losses during composting.