QS may refer to: Business QS mark (for "quality and safety"), on Chinese products Quacquarelli Symonds, an education and careers networking company QS World University Rankings, an annual publication Quality System (QS) Regulation, a business process Quantity surveyor, a professional in the construction industry concerned with costs and contracts Travel Service (IATA airline designator QS) Quadraphonic sound, the Sansui QS Regular Matrix system Politics Québec solidaire, a political party in Quebec, Canada Quis separabit?, an Irish Loyalist motto Science, technology, and mathematics Health and medicine ATCvet code QS Sensory organs, a section of the Anatomical Therapeutic Chemical Classification System for veterinary medicinal products Quantum satis, a Latin term meaning "the amount which is needed", used in food and drug regulation Quinolinate synthase, an enzyme Mathematics Quadratic sieve, an integer factorization algorithm Quicksort, a sorting algorithm Other uses in science and technology Quadraphonic sound, or "Quadphonic Synthesizer", a matrix quadraphonic gramophone record format developed by Sansui Quality Score, a variable used by search engines to set the rank and cost of ads Quantified self, a movement to incorporate technology into data acquisition on aspects of a person's daily life Quicksand, a colloid hydrogel consisting of fine granular material and water Quorum sensing, a system of interaction in natural and synthetic populations Sport Quality start, a baseball statistic calculated for starting pitchers Qualcomm Stadium, a stadium in San Diego, California Other uses Queen's Scout, a scout who has attained the Queen's Scout Award Queen's Serjeant, an obsolete legal position in the United Kingdom