a)Introduction to the problem:This study reveals the concept of mixed solvency, which explains that all substances whether liquids, gases or solids possess solubilizing power. Till now this concept have been utilized extensively in the field of pharmaceutical analysis and formulation with an aim to preclude the use of organic solvent, avoids the problem of residual solvent toxicity, reduce the individual concentration of solubilizers and thereby reduce their associated toxicity, replace relatively toxic class-II solvent by safer class-III solvent, potentiation of weaker solvent by use of proper choice of solubilizers and at last economic as well as eco-friendly. This concept can also be applied in formulation development of NDDS like microspheres, SEDDS etc and herbal extraction. In future, this concept shall prove a boon in pharmaceutical field and also in non-pharmaceutical field. b)Abstract:The objective is to explore mixed solvency concept in preparation of floating microspheres of furosemide. The prepared microspheres showed better result and prolongs the drug release (12h). c)Target groups: Pharmaceutics & pharmaceutical analysis.