Trade Sectrets and Patent Protection

What is the relationship between trade secrets and patents? Are they mutually exclusive or do they complement each other? Do innovative companies have to decide between trade secrets and patents or is there a possibility to make use of both protection variants? Rainer Beetz deals with these questions on the occasion of the implementation of the Know-How Directive in Austrian law in his article "Geheimnisschutz und Patentrecht" in the journal ip Competence, Vol. 21, July 2019