Fluosol, a first, low-concentration fluorocarbon emulsion, was recently approved for oxygenating the myocardium during percutaneous transluminal coronary angioplasty. Improvements in fluorocarbon and emulsion technology have led to the development of significantly more stable, more efficient second-generation injectable O2 carriers. This progress extends the potential of fluorocarbons in medicine to new applications both in diagnostics and in therapeutics. Future objectives will aim at adjusting and optimizing the preparation's characteristics for each specific application. The emulsifier, or surfactant, which determines the external appearance of the fluorocarbon droplets, will play a key role in the mastery of emulsion properties. Extensive research efforts are therefore being directed toward the synthesis and evaluation of new families of surfactants or co-surfactants specifically designed for emulsifying fluorocarbons.