He passed his First State Examination in Münster and obtained a doctorate in law in 1976, with a dissertation called "Representation and integration of foreign nationals in the Federal Republic of Germany with special regard to suffrage – also a comparative study about local election rights in the member states of the European Communities".

In 1998 and 2002 he won a seat through his placing on the CDU Party List of Baden-Würrtemberg in Germany's mixed member proportional representation voting system.

[1] Lamers was elected Deputy Chairman of the Defence Committee of the Bundestag in 2005 and is still holding this office.

[2] Lamers also acted as President of the Atlantic Treaty Association from 2008 to 2014, succeeding Robert E. Hunter, who held the office from 2003 to 2008.

In March 2019, Lamers announced that he would not stand in the 2021 federal elections and resign from active politics by the end of the parliamentary term.