Natural wine is wine made with minimal chemical and technological intervention in growing grapes and making them into wine. The term is used to distinguish such wine from organic wine. Organic wine is organic in the sense of having been produced made from organically grown grapes, but may be subject to chemical and physical manipulation in the winemaking process.
At the present time (2013) there exists no official or legal definition of natural wine; neither has any legislation been passed to date by any regional, national or supra-natural authority, and there are no organizations that can certify that a wine is natural.
However, there are many unofficial definitions or codes of practice published by the different associations of natural wine producers:
- Association des Vins Naturels (France) 
- Les Vins SAINS (France) 
- La Renaissance des Appellations (France) 
- Vini Veri (Italy) 
- Vinnatur (Italy) 
- Simbiosa (Slovenia) 
- Productores de Vinos Naturales (Spain) 
The following articles also cover the definition, or lack of definition, of natural wines:
Decanter Magazine, by Isabelle Legeron MW http://www.decanter.com/people-and-places/wine-articles/529224/natural-wines
Catavino, Tara O'Leary http://catavino.net/natural-wine-in-spain/
The following basic criteria are generally accepted by most natural wine producers and organizations:
- Organically or biodynamically grown grapes, with or without certification.
- Dry-farmed, low-yielding vineyards.
- No added sugars, no foreign yeasts, no foreign bacteria.
- No adjustments for acidity.
- No additives for color, mouth-feel, minerality, etc.
- No external flavor additives, including those derived from new oak barrels, staves, chips, or liquid extract.
- Minimal or no fining or filtration.
- No heavy manipulation, such as micro-oxygenation, reverse osmosis, spinning cone, cryoextraction.
- Minimal or no added sulphites aka sulfites.
International Natural Wine Fairs
- RAW (London, UK) 
- REAL (London, UK) 
- La Remise (Marseilles, France) 
- Vini Circus (Dingé, France) 
- A la Rencontre des Vins Naturels (Grenoble, France) 
- La Beaujoloise (France) 
- La Dive Bouteille (France) 
- Villa Favorita (Italy) 
- Salon de Vinos Naturales (Barcelona, Spain) 
The following people were or are particularly instrumental in the inspiration, production or communication of contemporary natural wine:
- Rudolf Steiner, curator of biodynamics.
- Maria Thun, author of the biodynamic calendar.
- Masanobu Fukuoka, Japanese philosopher of farming.
- Jules Chauvet, developer of carbonic maceration fermentation, sulphite free winemaking, and author.
- Claude Bourguignon, French agricultural scientist, consultant and author.
- Nicolas Joly, wine producer, head of Renaissance des Appellations Controlees, and spokesman for biodynamics.
- Marcel Lapierre, wine producer, mentor, and early adopter of low to no sulphite winemaking.
- Alice Feiring, American writer.
- Josko Gravner, Italian wine producer and mentor.
The term "Natural wine" is considered by Tom Wark to be a misleading term. There is no established certification body and the term has no legal status. Winemakers who describe themselves (or are described by others) as "natural" often differ in what they consider to be an acceptable level of intervention. The term might also confuse consumers into assuming that the wine is organically grown.
- Breton, Félicien: Organic wines
- Authentic Wine by Jamie Goode and Sam Harrop MW, ISBN 978-0-520-26563-9.
- The One Straw Revolution by Masanobu Fukuoka, ISBN various.
- Wine from Sky to Earth by Nicolas Joly, ISBN 0-911311-60-2.
- The Battle for Wine and Love: Or, How I Saved the World from Parkerization, by Alice Feiring, ISBN 978-0-15-101286-2
- Naked Wine by Alice Feiring, ISBN 978-0-306-81953-7.
- Real Wine by Patrick Matthews, ISBN 1-84000-257-3.