In the first Van Agt cabinet, Gardeniers was minister of Culture, Recreation and Social Work. After that she was Minister of Health and Environmental Hygiene.
As a minister, she implemented changes and cuts in healthcare. For example, the Provisions for the Disabled Act (WVG) was established during her ministry. Municipalities became responsible for helping disabled people. The WVG was a precursor to the current Social Support Act (WMO).
The Riaggs, regional institutions for outpatient mental health care, were also set up among Gardeners. They had to be accessible institutions for solving psychological problems, for which people could not go to a doctor or a social worker.
They were a success: in the 80s and 90s, hundreds of thousands of people flocked to the Riaggs and they were sometimes called "first aid in pain". Most of the Riaggs have since merged into larger associations in mental health care.
Gardeniers has also reformed broadcasting policy. This was necessary because of the rise of regional channels and cable television. The minister gained greater influence on the admission of new broadcasters.
Mathilde Gardeniers-Berendsen came to the Lower House in 1971 for the KVP. That party became part of the CDA in 1980. After her ministry, she was a member of the Council of State. She was a prominent member of the CDA. She devoted herself to the party until she was old.
The Gardeniers commission was established by the CDA in the 1990s. Til Gardeniers was chairman and had to investigate why the CDA had lost so much in the 1994 parliamentary elections under party leader Elco Brinkman.
Among other things, Gardeniers came to the conclusion that the CDA had become a "somewhat complacent driver party", that it had just come to be in power. The party also lacked unity and there was insufficient "listening skills" in the party administration.
Gardeners did not want to judge people. In general, the CDA's defeat in 1994 mainly refers to Prime Minister Ruud Lubbers, who openly dropped Brinkman.