This review on odour covers many aspects. The chapters subject are presented as follow: Odor and Odor Perception, Psychological Impact of Swine Odors, Odor Detection and Quantification, Legal Mechanisms for Odor Regulation, Relation Between Local Climatology and Odor Transport, Sources of Odor Associated with Pig Production, Techniques of Odor Reduction and Their Applicability, Chemical and Biological Additives to Achieve Odor Reduction, Effect of Feeding/Diet on Odors from Swine Manure, Air Treatment Processes, Integrating Site Selection, Facility Design and Odor Control Technologies, Separation Distances and Land Areas: A Manure Nutrient Balances Approach, The Real Odor Control Questions, and Research Opportunities Having Potential to Reduce Odor Complaints.