After training as a communications information electronics technician, Harald Flex graduated in 1978 with a degree in electrical engineering, specializing in communications engineering.

In industry, he has worked as a service technician, programmer, product manager in marketing and head of a business unit, covering a wide range of tasks in IT. In addition, he has programmed and distributed various specialist applications in the benefits area for health insurance companies as a permanent sideline.

In 1994, as project manager for a group of health insurance companies, he took over the conception and development of the acceptance points for electronic data exchange with service providers.

In November 1996, Harald Flex was appointed founding managing director of ITSG - Informationstechnische Servicestelle der gesetzlichen Krankenversicherung GmbH - as a joint and neutral working group of all health insurance companies for digitization in the health and social care sector. He led the ITSG, which today employs more than 180 people as a full service provider and has a turnover of around €50 million, until December 2022, when he will retire.

In 2005, Harald Flex was also appointed founding managing director of gematik - Gesellschaft für Telematikanwendungen der Gesundheitskarte GmbH - and managed the development of this company until 2006.