Fast-flux service networks demonstrate an evolutionary step for online crime operations. Fast-flux service networks create robust, obfuscating service delivery infrastructures that make it difficult for system administrators and law enforcement agents to shut down active scams and identify the criminals operating them. The robustness, obfuscation capabilities, scalability and increased availability of fast-flux service produce an increased Return on Investment (ROI) for the criminals who operate them. Just as in legitimate business, the Internet represents a huge economic business model for online crime, which unfortunately means that we can expect techniques such as fast-flux service networks to continue to evolve. Often emerging threats such as fast-flux service networks are a step ahead of security professionals, and it looks likely that this particular arms race will continue into the foreseeable future.