Vaccine Safety Net (VSN) is a global network of websites aimed at helping people judge the quality of online information on vaccine safety. It was established in 2003 by the World Health Organization (WHO), which had previously set up the independent Global Advisory Committee on Vaccine Safety (GACVS), prompted by concern from public health officials regarding the dissemination of potentially harmful health information via the web. By appraising websites, using credibility and content criteria defined by GACVS, the VSN has been developed to deliver information that is easy to access and up-to-date. As of 2020, the initiative has 89 member sites in 40 countries and 35 languages. Prior to inclusion in the list, each website is assessed for its credibility, accessibility, content and design. A peer-reviewed study of 26 websites listed by VSN in 2008 noted "the transparency of financing, the lack of links to the pharmaceutical industry, the transparency of site management and responsibility and the proven scientific quality and constant updating of contents" of its assessed resources. Purpose The WHO's VSN is a "trusted" website for reliable vaccine related sources. The purpose of the VSN is to evaluate the variable reliability of on-line vaccine related information and address concerns caused by websites which circulate partially complete or misleading content, including speculative rumours or falsified research, which may consequently damage vaccination programmes. It aims to regularly review the vaccine related content disseminated on-line by different health-related organizations around the world, thereby validating them by including them on their list as websites that observe "good information practices". History and membership In developed countries, more than 90% of young people use the internet regularly, running the potential for misinformation related to vaccination reaching a large proportion of society. This has also been challenging in low and middle income countries. In 1999, concern from public health officials regarding the dissemination of potentially harmful health information via the web led the WHO to establish the 'Global Advisory Committee on Vaccine Safety' (GACVS), the purpose of which is to deliver an assembly of independent professionals that can advise both the public and those involved in national vaccine policy, after assessing evidence pertaining to vaccine safety concerns that require a quick and impactful response. In 2003, the WHO created the VSN, devised to "help counteract misinformation about vaccines" and deliver easily accessible information to up-to-date accurate evidence, by appraising websites that provide material on vaccination.