Horizon scanning (HS) or also horizon scan is a method from futures studies, sometimes regarded as a part of foresight.  It is the early detection and assessment of emerging technologies or threats for mainly policy makers in a domain of choice.    Such domains include agriculture,  environmental studies,  health care,  biosecurity,  and food safety. 
Some sources mention HS as an alternative name for environmental scanning (ES),  or view HS as a subset of ES,  or at least suggest ES to have a similar goal to HS.  In summary, ES has key differences to HS.  ES is rather concerned to provide industry specific information for short-term decision making in a competitive environment.   
One of the first usages of the term horizon scanning as related to futures studies appeared in 1995 in a paper discussing trends in information technology and forecasting the year 2005.  Then, horizon scanning was used to name detection and early evaluation of health care technologies in a European workshop in September 1997, whose participants were 27 policy makers and researchers from 12 countries.  This workshop was organized as a part of the European health technology assessment project (HTA).  Policy makers and planners of health services were the main target groups for knowledge produced by horizon scanning. 
|2002||Department for Environment, Food and Rural Affairs||
Horizon scanning is "the systematic examination of potential threats, opportunities and likely future developments which are at the margins of current thinking and planning’ and, continuing, horizon scanning ‘may explore novel and unexpected issues, as well as persistent problems or trends." 
|2004||UK Government's Chief Scientific Advisor's Committee||"Horizon scanning is the systematic examination of potential threats, opportunities and likely future developments including – but not restricted to – those that are at the margins of current thinking and planning. Horizon scanning may explore novel and unexpected issues, as well as persistent problems or trends." |
|2015||Report by Fraunhofer Institute for Systems and Innovation Research ISI for the European Commission||"Horizon Scanning is the systematic outlook to detect early signs of potentially important developments. These can be weak (or early) signals, trends, wild cards or other developments, persistent problems, risks and threats, including matters at the margins of current thinking that challenge past assumptions." |
Horizon scanning is "a technique for detecting early signs of potentially important developments through a systematic examination of potential threats and opportunities, with emphasis on new technology and its effects on the issue at hand." 
A 2013's systematic study of 23 formally established health technology HS programs from different countries identified following common phases in a horizon scanning process: 
- Identify the users of the HS products.
- Estimate the time available for the HS effort.
- Conduct HS, and identify emerging technologies that potentially affect targeted domain.
- Filter the identified technologies by applying criteria for determining the relevance of the technologies to the HS effort.
- Prioritize the technologies that have passed through the filtering process by applying criteria based on stakeholders’ requirements and needs.
- Assess technologies of high priority for the stakeholders, and predict their potential impacts targeted domain.
- Use peer review to check for quality of the HS process and products.
- Disseminate the HS products to the relevant audiences in a timely fashion.
- Update the HS products on a regular basis or when a significant development occurs related to the technology.
|Interviews||Environmental Research Funders Forum Horizon Scanning Study |
|Issue tree||Foresight project on Brain Science, Addiction and Drugs |
|Literature searches and state-of-science reviews||Medical Technology Horizon Scanning |
|Expert workshops||Horizon scan of conservation issues in UK.  Assessment of 100 ecological questions of highest priority to global conservation. |
|Open fora||Future Wiki |
|Delphi questionnaire||50 key issues for the future of Mediterranean wetlands |
|Trend analysis||HSTOOL - semiautomatic discovery of scientific trends from clusters of publications |
|Scenarios ||Wildlife Conservation Societies’ Futures of the Wild |
|Systems/Maps||Foresight project on Tackling Obesities: Future Choices |
In order to centralize horizon scanning, UK has founded the English Horizon Scanning Centre (HSC) in 2005.  The Cabinet Office's Horizon Scanning Secretariat and the Government Office for Science's Horizon Scanning Centre were combined to the Horizon Scanning Programme team in 2014. 
Swedish Defence Research Agency has developed a software tool named HSTOOL for HS of scientific literature in 2019.  The scientific literature is searched, clustered in groups that correspond to subject subfields and evaluated based on the bibliometric numbers. The clustering is performed using Gibbs sampling Dirichlet multinomial mixture model algorithm. The citation statistics are provided derived from Thomson Reuters' Web of Science.
- Risk analysis
- Scientific lacuna
- Technology assessment
- Technology scouting
- William J. Sutherland
- Cuhls, Kerstin E. (2020). "Horizon Scanning in Foresight – Why Horizon Scanning is only a part of the game". Futures & Foresight Science. 2 (1): e23. doi: 10.1002/ffo2.23. ISSN 2573-5152.
- "Continuity Central". www.continuitycentral.com. Retrieved 25 February 2021.
- Sutherland, William J.; Aveling, Rosalind; Brooks, Thomas M.; Clout, Mick; Dicks, Lynn V.; Fellman, Liz; Fleishman, Erica; Gibbons, David W.; Keim, Brandon; Lickorish, Fiona; Monk, Kathryn A.; Mortimer, Diana; Peck, Lloyd S.; Pretty, Jules; Rockström, Johan; Rodríguez, Jon Paul; Smith, Rebecca K.; Spalding, Mark D.; Tonneijck, Femke H.; Watkinson, Andrew R. (January 2014). "A horizon scan of global conservation issues for 2014". Trends in Ecology & Evolution. 29 (1): 15–22. doi: 10.1016/j.tree.2013.11.004. PMC 3884124. PMID 24332318.
- Smith, J; Ward, D; Michaelides, M; Moore, A T; Simpson, S (September 2015). "New and emerging technologies for the treatment of inherited retinal diseases: a horizon scanning review". Eye. 29 (9): 1131–1140. doi: 10.1038/eye.2015.115. PMC 4565944. PMID 26113499.
- Text Mining for Horizon Scanning: An Insight Into Agricultural Research and Innovation in Africa. Publications Office of the European Union. 2020. ISBN 978-92-76-21446-5.
- Sutherland, William J.; Woodroof, Harry J. (1 October 2009). "The need for environmental horizon scanning". Trends in Ecology & Evolution. 24 (10): 523–527. doi: 10.1016/j.tree.2009.04.008. ISSN 0169-5347. PMID 19660827.
- Carlsson, P.; Jørgensen, T. (1998). "Scanning the horizon for emerging health technologies. Conclusions from a European Workshop". International Journal of Technology Assessment in Health Care. 14 (4): 695–704. doi: 10.1017/s0266462300012010. ISSN 0266-4623. PMID 9885460.
- "Horizon Scanning and ForesightAn overview of approaches and possible applications in Food Safety" (PDF). fao.org. FAO. Retrieved 25 February 2021.
- Schultz, Wendy L. (1 January 2006). "The cultural contradictions of managing change: using horizon scanning in an evidence‐based policy context". Foresight. 8 (4): 3–12. doi: 10.1108/14636680610681996. ISSN 1463-6689.
- Miles, Ian; Saritas, Ozcan (2 November 2012). "The depth of the horizon: searching, scanning and widening horizons". Foresight. 14 (6): 530–545. doi: 10.1108/14636681211284953.
- van Rij, Victor (1 February 2010). "Joint horizon scanning: identifying common strategic choices and questions for knowledge". Science and Public Policy. 37 (1): 7–18. doi: 10.3152/030234210X484801. ISSN 0302-3427.
- Rowe, Emily; Wright, George; Derbyshire, James (1 December 2017). "Enhancing horizon scanning by utilizing pre-developed scenarios: Analysis of current practice and specification of a process improvement to aid the identification of important 'weak signals'". Technological Forecasting and Social Change. 125: 224–235. doi: 10.1016/j.techfore.2017.08.001. ISSN 0040-1625.
- Choo, Chun Wei (2002). Information Management for the Intelligent Organization: The Art of Scanning the Environment. Information Today, Inc. ISBN 978-1-57387-125-9.
- Miles, Ian; Saritas, Ozcan (2 November 2012). "The depth of the horizon: searching, scanning and widening horizons". Foresight. 14 (6): 530–545. doi: 10.1108/14636681211284953. ISSN 1463-6689.
- Ramírez, Rafael; Selsky, John W. (February 2016). "Strategic Planning in Turbulent Environments: A Social Ecology Approach to Scenarios". Long Range Planning. 49 (1): 90–102. doi: 10.1016/j.lrp.2014.09.002.
- Gates, William H. (1 January 1995). "Horizon Scanning: Opportunities Technology Will Bring by 2005". Journal of Business Strategy. 16 (1): 19–21. doi: 10.1108/eb039676. ISSN 0275-6668.
- Könnölä, Totti; Salo, Ahti; Cagnin, Cristiano; Carabias, Vicente; Vilkkumaa, Eeva (1 March 2012). "Facing the future: Scanning, synthesizing and sense-making in horizon scanning". Science and Public Policy. 39 (2): 222–231. doi: 10.1093/scipol/scs021. hdl: 11475/8386.
- Palomino, Marco A.; Bardsley, Sarah; Bown, Kevin; De Lurio, Jennifer; Ellwood, Peter; Holland‐Smith, David; Huggins, Bob; Vincenti, Alexandra; Woodroof, Harry; Owen, Richard (24 August 2012). "Web‐based horizon scanning: concepts and practice". Foresight. 14 (5): 355–373. doi: 10.1108/14636681211269851.
- "Models of Horizon Scanning How to integrate Horizon Scanning into European Research and Innovation Policies" (PDF). Fraunhofer ISI. Retrieved 26 February 2021.
- National Academies of Sciences, Engineering; Sciences, Division on Engineering and Physical; Division, Health and Medicine; Affairs, Policy and Global; Studies, Division on Earth and Life; Resilience, Forum on Cyber; Policy, Board on Health Sciences; Board on Science, Technology; Resources, Board on Agriculture and Natural; Sciences, Board on Life; Committee on Safeguarding the Bioeconomy: Finding Strategies for Understanding, Evaluating (2020-01-14). "HORIZON SCANNING AND FORESIGHT METHODS". National Academies Press (US). Retrieved 22 June 2021.
- Sun, F; Schoelles, K (2013). AHRQ Health Care Horizon Scanning System A Systematic Review of Methods for Health Care Technology Horizon Scanning (PDF).
- "An Environment Research Funders' Forum Report: Horizon Scanning Study". ERA Visions. 2007. Retrieved 7 March 2021.
- "Brain science, addiction and drugs". GOV.UK. 2005. Retrieved 7 March 2021.
- Brown, I.; Smale, A.; Verma, A.; Momandwall, S. (December 2004). "Medical Technology Horizon Scanning". Australasian Physical & Engineering Sciences in Medicine. Retrieved 3 June 2021.
- Sutherland, William J.; Bailey, Mark J.; Bainbridge, Ian P.; Brereton, Tom; Dick, Jaimie T. A.; Drewitt, Joanna; Dulvy, Nicholas K.; Dusic, Nicholas R.; Freckleton, Robert P.; Gaston, Kevin J.; Gilder, Pam M.; Green, Rhys E.; Heathwaite, A. Louise; Johnson, Sally M.; Macdonald, David W.; Mitchell, Roger; Osborn, Daniel; Owen, Roger P.; Pretty, Jules; Prior, Stephanie V.; Prosser, Havard; Pullin, Andrew S.; Rose, Paul; Stott, Andrew; Tew, Tom; Thomas, Chris D.; Thompson, Des B. A.; Vickery, Juliet A.; Walker, Matt; Walmsley, Clive; Warrington, Stuart; Watkinson, Andrew R.; Williams, Rich J.; Woodroffe, Rosie; Woodroof, Harry J. (2008). "Future novel threats and opportunities facing UK biodiversity identified by horizon scanning". Journal of Applied Ecology. 45 (3): 821–833. doi: 10.1111/j.1365-2664.2008.01474.x. ISSN 1365-2664.
- Sutherland, William J.; Armstrong‐Brown, Susan; Armsworth, Paul R.; Tom, Brereton; Brickland, Jonathan; Campbell, Colin D.; Chamberlain, Daniel E.; Cooke, Andrew I.; Dulvy, Nicholas K.; Dusic, Nicholas R.; Fitton, Martin; Freckleton, Robert P.; Godfray, H. Charles J.; Grout, Nick; Harvey, H. John; Hedley, Colin; Hopkins, John J.; Kift, Neil B.; Kirby, Jeff; Kunin, William E.; Macdonald, David W.; Marker, Brian; Naura, Marc; Neale, Andrew R.; Oliver, Tom; Osborn, Dan; Pullin, Andrew S.; Shardlow, Matthew E. A.; Showler, David A.; Smith, Paul L.; Smithers, Richard J.; Solandt, Jean-Luc; Spencer, Jonathan; Spray, Chris J.; Thomas, Chris D.; Thompson, Jim; Webb, Sarah E.; Yalden, Derek W.; Watkinson, Andrew R. (2006). "The identification of 100 ecological questions of high policy relevance in the UK". Journal of Applied Ecology. 43 (4): 617–627. doi: 10.1111/j.1365-2664.2006.01188.x. ISSN 1365-2664.
- "Futura Wikia". Retrieved 7 March 2021.
- Taylor, Nigel G.; et al. (2021). "The future for Mediterranean wetlands: 50 key issues and 50 important conservation research questions". Regional Environmental Change. 21 (2): 33. doi: 10.1007/s10113-020-01743-1. PMC 7982080. PMID 33776560.
- Karasalo, Maja; Schubert, Johan (September 2019). "Developing Horizon Scanning Methods for the Discovery of Scientific Trends". 2019 International Conference on Document Analysis and Recognition (ICDAR): 1055–1062. doi: 10.1109/ICDAR.2019.00172. ISBN 978-1-7281-3014-9. S2CID 207977849. Retrieved 20 May 2021.
- Palomino, Marco A.; Bardsley, Sarah; Bown, Kevin; De Lurio, Jennifer; Ellwood, Peter; Holland‐Smith, David; Huggins, Bob; Vincenti, Alexandra; Woodroof, Harry; Owen, Richard (1 January 2012). "Web‐based horizon scanning: concepts and practice". Foresight. 14 (5): 355–373. doi: 10.1108/14636681211269851. ISSN 1463-6689. Retrieved 16 May 2021.
- Futures of the Wild: A Project of the Wildlife Conservation Society Futures Group. Wildife Conservation Society Futures Group and Bio-Era. 2007.
- "Reducing obesity: future choices". GOV.UK. 2007. Retrieved 7 March 2021.
- Miles, Ian; Saritas, Ozcan (2 November 2012). "The depth of the horizon: searching, scanning and widening horizons". Foresight: The Journal of Future Studies, Strategic Thinking and Policy. 14 (6): 530–545. doi: 10.1108/14636681211284953.
- "Horizon Scanning Programme team". GOV.UK. Retrieved 26 February 2021.
- Lehmphul, Karin (24 May 2016). "Horizon Scanning / Trendanalyse". Umweltbundesamt (in German).
- "HSTOOL for Horizon Scanning of Scientific Literature". www.foi.se. Retrieved 20 May 2021.
- Text mining for horizon scanning : an insight into agricultural research and innovation in Africa (PDF). Luxembourg. 2020. ISBN 978-92-76-21446-5.
- "methodology_emerging-innovations_US_health-care" (PDF). www.ispor.org. Retrieved 26 February 2021.