This paper presents a liquid-phase approach to particle production using electrohydrodynamic (EHD) mixing. EHD flows are used to disperse one miscible, reactive fluid into another, based on the capability to develop significant fluid velocities and turbulence by charge injection into dielectric fluids. Alcohol solvents, commonly used for sol-gel reactions, are very suitable for applying this EHD mixing approach. The rapid micromixing in the vicinity of the electrified injector allows the liquid-phase reactions to be conducted uniformly at high rates. This approach allows continuous production of non-agglomerated, monodispersed, submicron-sized particles.Experiments aimed at investigating the capability for EHD mixing to improve particle production were conducted in a continuous-flow system using the hydrolysis and condensation of zirconium tetra-n-butoxide in alcohols. Because of the rapid kinetics of this reaction system, the quality of ultrafine particles produced is greatly affected by the degree of early-stage mixing. Mixing of the reactant streams was shown to improve with increasing applied voltage, and a corresponding improvement in the homogeneity of the produced particles was determined. The EHD mixing approach was shown to have several possible advantages in comparison with batch reactions. The reaction can be conducted to produce quality particles at higher concentrations, and the particles produced by EHD mixing are more homogeneous. In addition, under the rapid micromixing conditions, it is possible to manipulate nucleation rates through the introduction of concentrated reactants, resulting in the capability to produce significantly smaller particles. This study indicates that reactors utilizing EHD mixing could be used for continuous, rapid production of homogeneous, ultrafine particles. (C) 2003 Elsevier B.V. All rights reserved.