They began as a rights - based approach developed by UNICEF to guarantee children 's rights to survival , development , participation and protection , especially at times of crisis or instability .
CFS have been used widely since 1999 .
CFS began as a rights - based approach developed by UNICEF to guarantee children 's rights to survival , development , participation and protection , especially at times of crisis or instability .
CFS have been used widely since 1999 .