Members of Think Foundation have been involved in the field of blood donation for more than 30 years.  It all started when a group of friends sharing a common concern came together and hit upon the idea of a blood donation drive in their residential area.  A list of donors was maintained after the drive, and donors were identified and sent to hospitals to meet specific requirements.

In August 1999, CITIZEN was formed as a charitable trust by the same group of friends, with the objective of giving a major thrust to the cause of blood donation and thalassaemia.  A large number of activities were organized with the support of a floating population of volunteers.

Think Foundation was established with the objective of giving a structure to the activities of CITIZEN, so that it could be sustained, scaled-up and replicated elsewhere in the country.