We believe that practice itself is the true definition of sonic acupuncture. While the act of definition may restrict what the artistic practice of public space sonic acupuncture might be, we nonetheless require a description of what we call sonic acupuncture. This description is continually revisited including each finding and each new project. Hopefully, in the future, public space sonic acupuncture will have so many examples that there will be no need for any description or definition.
In order to define sonic acupuncture, we must start by defining acupuncture: this is a local action that has the power to change the situation globally, where a pressure point on a key spot expands beyond the locality of that situation. Hence, sonic acupuncture is the application of sonic pressure on key points to affect the global sonic situation.
Urban acupuncture is an established public space architectural practice.     Urban sonic acupuncture is analogous to public space acupuncture in the aural architecture field. Aural architecture deals the behaviour of sound in space and, since it takes into account physical acoustics and cultural acoustics, it also deals with how sonic behaviour is understood and interpreted by the local community. It assigns four basic functions for sound: social, navigational, aesthetic, and musical spatiality. Sonic behaviour within a site is usually a result of many decisions, usually economic, political, and socio-cultural constraints, that have nothing to do with sound but nonetheless impact it. Therefore, unlike visual architecture, the aural architecture is not the design of one person but rather a social force. Adding an aural perspective to urban acupuncture leads to new forms of knowledge about urban dwelling and sense of place creation.
Using sound in the public space can be a source of controversy related to consent: although the user can close their eyes, they cannot close their ears. This means, in terms of aural architecture, that whoever has the power to control the size of the acoustic arena has a political power; in other words, ‘sound does not stop at visual or economic boundaries’.  Addressing that, the project ‘Beyond the Noise: Open Source Soundscape. A Novel Mixed Methodology to identify, evaluate and plan quiet areas in cities’  presents a methodology for identifying and locating silent areas of the city and placing them on an interactive map. In the same direction, Jaime Lerner speaks about ‘acupuncture of silence’, by which he does not mean ‘absolute silence, but the absence of the distortion of the natural urban sounds’.  While much research has been made into quantitative sonic aspects like noise pollution and its avoidance, very little research has been done on qualitative aspects of sound in public spaces.  
The sound art duo O+A call attention to the concept of sonic commons. This is similar to the concept of ‘acoustic arena’ in aural architecture but incorporates a sense of social responsibility. They define the sonic commons as ‘a complex multi-user environment leaving an accidental soundscape as a by-product’.  The artists are very well aware that altering the sound of a space can affect social interactions, how architecture is perceived, and bodily relations. Changing the sound changes the emotional environment. They practice very local permanent sound installations in sonically conflicted spaces, transforming the site’s relation to dwellers and passers-by. The MASS MoCA director Joe Thompson called the Harmonic Bridge (1998) a ‘wonderful piece of sonic jujitsu’. .
We are intrigued by this idea of openness towards urban sound in opposition to isolation by sound blocking, cocooning, or by using music players with headphones. The use of headphones gave birth to what might be called ‘the headphone city’ and it is contributing to new forms of urban detachment and isolation. Sonic Greenhouse contains elements that need further exploration in urban settings, yet these elements present a statement of how our relation to urban sound can benefit from leaning our attention into its qualitative aspects.
Ultimately, public space sonic acupuncture is an artistic invitation to listen with different ears and to allow a subtle sonic intervention to drive our attention towards different areas and hidden corners of our cities, fostering more conscious urban dwelling and social dialogues.