The book draws attention to the growing importance of clusters today and examines academic studies on clusters. The purpose of the book is to find out the benefits of clusters, whether they catalyze for local, regional and even national development as claimed in theory, in short, whether they are a panacea. First, a thorough literature review is offered and then successful examples of clusters in the world are examined: the Baden-Württemberg automotive cluster in Germany, the Hollywood film cluster in the USA, the Hamburg aviation cluster in Germany, the automotive cluster in Japan, the Castellon ceramic cluster in Spain, and the Sassuolo ceramic cluster in Italy. Afterward, clusters in Turkey are briefly analyzed. Finally, the author's answer to the question of whether clusters are a panacea is presented and the conditions required for clusters to be successful are discussed.