Although there is much confusion about it in everyday language, the distinction between public and common goods is clear enough within Economics. While the former involves the fact of being open to all and state management, the latter requires common but still limited management. The different kind of administration can also be explored through the reference to a different kind of agent meant as the one who makes use of the different goods: if in the case of public goods, we (...) have individuals, as an aggregate, in that of commons we necessarily need to assume the existence of a plural form of subject, who can in fact act in concert in the management of the good itself. Exploring this distinction in its details and consequences, the paper sets out to apply it to a typical public good – green areas in cities – and to show the theoretical advantages that such a consideration of the commons can have, including through a concrete case such as community gardens. (shrink)