In search of new bio-active molecule, the development of hybrid molecules through the combination of three pharmacophores in one frame may lead to compounds with interesting biological properties. The aim of this book is to provide a brief biological profile of newly synthesized thiazole and 4-oxo-thiazolidine clubbed derivatives. We have included the synthesis, characterization and antimicrobial screening of thiazole and 4-oxo-thiazolidine clubbed derivatives.