[5] Beginning in 1954, Lanner attended the Higher Federal College for Alpine Agriculture in Seefeld in Tirol, graduating in 1956.

In 1960, he attended the University of Natural Resources and Life Sciences, Vienna (BOKU), receiving a Diplom-Ingenieur later that year.

[1] In 1971, Lanner was elected to the National Council of Austria as a member of the Austrian People's Party (ÖVP).

From 1969 until 1976, Lanner was the director of the Austrian Farmers' Union [de], and he also served as the head of the Department of Agricultural Policy and Integration.

[2] Throughout his career, Lanner was known for his advocacy for Austrian agriculture, and he was regarded as "one of the most prominent representatives of the farmers and rural areas".

[2] Karl Nehammer, the chancellor of Austria, stated that Lanner was a "connecting politician who always put the common ground in the foreground and therefore enjoyed the highest reputation across party lines".