Background: Formal CEO board membership is a unique feature of Swedishboards. The share of firms having Formal CEO board membership hassignificantly decreased in the last 20 years and thus, this feature might haveevolved to be used as a signal of high CEO quality. CEO quality is in turnlikely to, through Formal CEO board membership, serve as a moderator of therelationship that both CEO power and CEO discretion has to firm performancewhich has previously been somewhat ambiguous. Purpose: The purpose of this study is to explain how the CEO’s power anddiscretion is related to firm performance and if this relation is moderated byFormal CEO board membership. Method: To fulfill the purpose of this thesis, a deductive research approachwas used. The theoretical model used is built on four theories namely,Stewardship theory, CEO power, CEO discretion and Signaling theory. With a five-year interval stretching between 1998 to 2018, the quantitative empiricalmethod relies on compensation and financial data from Swedish firms. Conclusion: The results indicate that the relation that both CEO power andCEO discretion have to firm performance, consistent with the theoreticalmodel, is positive. The results further indicate that Formal CEO boardmembership as a signal of CEO quality can moderate these relationships. Thisfinding is, however, exclusive to the years after 2008.