This review covers recent developments on the topic of DNA gel particles formed in water–water emulsion-type interfaces. A general understanding of interactions between DNA and oppositely charged agents has given us a basis for developing novel DNA-based materials, including gel particles. The association strength, which is tuned by varying the chemical structure of the cationic cosolute, determines the spatial homogeneity of the gelation process, creating DNA reservoir devices and DNA matrix devices that can be designed to release DNA (either single- (ssDNA) or double-stranded (dsDNA)). Besides an introduction concerning general aspects about DNA–cationic complexes and the formation of gels in water–water emulsion-type interfaces and some conclusions, the review contains sections reviewing the preparation of DNA gel particles using 1) surfactants, 2) polysaccharides and 3) proteins. The particle morphology, swelling/dissolution behaviour, degree of DNA entrapment and DNA release responses as a function of the nature of the cationic agent used are discussed. Finally, current directions on the preparation of DNA gel particles, including the decrease of size and the improvement of the biocompatibility of these systems have been reviewed.