Noun
An alternative approach to international relations characterised by dialoguing and building relationships (with the aim of solving or advocating a solution to a political-diplomatic issue) not merely outside of traditional diplomatic channels (i.e., diplomatic missions), but entirely without government direction or sponsorship (cf. public diplomacy).
As articulated by w:Daryl Copeland: a cross-cultural, enabled, and grassroots approach to diplomatic practice characterized by autonomy, agility, adaptability and resilience; a premium on intelligence gathering and analysis; access to global political economy of knowledge; the ability to act with souplesse.
Source: en.wiktionary.org