The main focus of this book is to draw the attention towards ionic liquids (ILs) as additives in altering the physico-chemical properties of conventional surfactant solutions, their self-aggregation, interactions with drugs and conventional surfactants, an insight into the use of ionic liquids particularly surface active ionic liquids as solubilizers and biological activity enhancers, and in various synthetic processes and how they affect the outcome. Surface active ionic liquids (SAILs) and their interaction modes and how they play a role in altering the physico-chemical properties and in solubilizing the various kinds of biomolecules is highlighted. Ionic liquids as colloidal carriers in drug delivery and as excipients in pharmaceutical preparations are also given due importance.