Overground Network owned by Transport for London
Overground Network (abbreviated on or ON) was a branding initiative launched in 2003 by the Strategic Rail Authority (SRA) and Transport for London (TfL), the public transport authority in London, England. Its aim was to encourage use of National Rail services in South London. The project was a partnership between the SRA, TfL, three train operating companies (Connex South Eastern, South Central Trains and South West Trains), the South and West London Transport Conference (SWELTRAC) and the South East London Transport Strategy (SELTRANS). The scheme is no longer being promoted and the Overground Network project has since been abandoned.
Note that in common parlance within London, the term "overground" may be used in reference to any National Rail line, in order to distinguish it from the Underground.