In this review, we attempt to describe the structure of various spinel ferrites like zinc ferrite, nickel-zinc ferrite, manganese-zinc ferrite and cobalt ferrite. It also describes the important magnetic properties of these spinel ferrites. The focus then shifts to the use of microemulsions as nanoreactors for the synthesis of spinel ferrites. This work gives a short review on the various synthesis methods of spinel ferrites in microemulsions in the recent years. (c) 2006 Elsevier B.V. All rights reserved.