Over the last few decades, the use of modern techniques in sciences has increased exponentially, and chromatographic techniques are use widely for analytical purposes. Today, several thousand new compounds as well as numerous pharmaceutical products are analyzed on routine basis by these techniques. This book is based on the same technique and contains new methods for alone as well as for simultaneous determination of a well known antibiotic, sparfloxacin, flouroquinolone. Present work deals with the interaction of sparfloxacin with NSAIDs, H2-receptor antagonists, essential and trace elements and heavy metals by RP-HPLC at different pHs. For study these interactions, numbers of methods were developed for quantizing sparfloxacin alone and with NSAIDs and H2 receptor antagonist on HPLC, which were optimized and validated according to ICH guidelines. These methods can be applied for the estimation of each interacting drug in routine industrial analysis and in different clinical labs and in human serum. The current book may help as a lime light for the industry as well as for the healthcare professionals or anyone else who may considering to serve in the field of analytical chemistry.