The coordination chemistry of azo-heterocyclic compounds of silver (I), cadmium(II), manganese(II), ruthenium(0) and ruthenium(II) have been described. A newly designed unsymmetrical bi-heterocyclic azo compound, pyridyl-azo-imidazole has also been characterized in this book. The complexes have been characterized by microanalytical and spectroscopic data. Manganese(II) forms tetrahedral complex and has been characterized by their spectra, magnetic and electrochemistry. Pyridyl-azo-imidazoles form metallo-macrocyclic compound with silver(I) and with cadmium(II) a tetrahedral structure have been characterized by their X-ray structure. Ru(0)-CO and Ru(II)-complexes of 2-{3/-(Pyridylazo)}imidazole alongwith isomeric dichloro-bis-chelated azoimine-Ru(II) complexes are described and characterized by their spectra and electrochemistry.