Electrospinning is a simple unit operation process by which polymeric nanofibers with diameters ranging from a few nanometers to hundreds of micrometers can be fabricated using an electrostatically operated jet of polymer solution or polymer melt. Nanofibers because of their interesting features, such as surface-to-volume ratio, high surface area, microporosity, and nonwoven structure, provide numerous opportunities to design novel carrier systems for large commodities of therapeutics. Physicochemical properties of nanofibers depend on several process and formulation parameters, such as applied voltage, flow rate, polymer selection, and concentration of polymer used. The applications of nanofibers in drug delivery are nearly unbounded. This review summarizes the most recent work done on the various physicochemical parameters of electrospinning and polymers used in making wide varieties of nanofibers along with their role in developing more effective, novel drug delivery systems.