Historically, the field of nanomedicine and the global endeavor to generate NPs for drug delivery arose from one of the greatest struggles in medicine: gene therapy. At the core of that approach was the idea that viruses could be used as Trojan horses to deliver the correct sequence of the gene into the cells that harbored the mutated copy. In order to identify the virus that offered the best delivery service, a cadre of viral strains and species were tested, adapted, and engineered to fit the aims and hit the targets. It took decades of trial and error, of progressive adjustments, and a few tragic mistakes to identify the viruses that could provide the ideal backbone to develop viral vectors able to ferry genetic cargo into the target cell.122 In the midst of that global challenge, nanotechnology offered a safer and more controllable alternative: to generate bespoke structures that could replace viral vectors and do the same job, delivering a payload from the point of injection to the site of action.