Communicable disease control relies on effective response systems and effective response systems rely on effective disease surveillance. Surveillance is first step towards prevention. In addition to conventional routine indicator based surveillance system, countries must develop additional tools in terms of supplementary surveillance system for providing information on early detection of outbreaks in India so that a timely and an appropriate action can be taken. Presently Integrated Disease Surveillance Project (IDSP) at National Centre for Disease Control, Delhi, India is carrying out country wide surveillance. IDSP has developed four supplementary event reporting tools to strengthen and increase the sensitivity of its routine weekly indicator based surveillance system. These event based reporting tools are Early Warning Signals/Outbreak reporting, Media Surveillance, Toll free number (1075) and Community Based Surveillance. These supplementary tools have proven to be efficient and effective in timely detection of many public health threats.