A new process is presented where the controlled coagulation of droplets is achieved through electrical forces. The charged droplets are produced by electrosprays operated in the cone-jet mode. The coagulation of oppositely charged droplets leads to the neutralization of the electrosprays. Furthermore, this coagulation enables controlled mixing on a microscale and subsequent chemical reactions inside the combined droplets. This process has many potential applications in the production of "tailored" particles, particles of uniform size and composition.