Colloid science has now been reframed in advance form as nanotechnology. Novel nanoparticulate carrier systems could make an important impact on clinical practice, not only in the field of targeted drug delivery but also for the delivery of diagnostic agents, gene therapy and vaccine delivery as well. Polymer based nanoparticles are full of numerous advantages in delivery science but at the same time they suffer from toxicity considerations and problems in industrial scale up of the formulations. Lipid based carrier systems i.e. emulsions, liposomes etc. have been tried to solve such problems related to the delivery technology. Currently lipid-based nanoparticles gained much interest as they combine both the technology of lipid sciences and nanosciences, and hence may be better alternative carriers. Many aspects related to the development of solid lipid nanoparticles (SLNs) like production technology, effect of process parameters, selection of ingredients and route of delivery are important for the industrial applications of nanoscience. In the present review a detail discussion of methods of production of solid lipid nanoparticles, influence of ingredients of composition on product quality, therapeutic moiety effect, characterization parameters and effects of sterilization have been focused. Role of solid lipid nanoparticles for controlled and targeted drug delivery, utility as a novel transfection agent and their potential as adjuvant for vaccine delivery are summed up in addition. Clinical therapeutics of SLNs in terms of advantages and limitations of various routes of delivery of SLNs has also been explored for the further advancement of practical applications of solid lipid nanoparticles.