Bioterrorism is a form of terrorism in which deliberate release of viruses, bacteria, toxins or other harmful agents used to cause illness or death in people, animals, or plants occurs. These biological agents are usually found in nature, but they can be altered and engineered in order to increase their ability to cause disease, spread fast and easy throughout the population or to make them resistant to known medications. Biological agents are attractive to terrorist because of their ease of use, storage and dissemination, and they also cause panic amongst people even if the actual attack is not very successful. There are different types of agents; some are more fatal than others, or better suited for mass attacks, but none should be underestimated. Special attention should be directed towards genetic engineering and genomics, and possibilities that modern science gives to people who do not have best intentions. Bioterrorism and biological warfare is not a new idea, and it has been used throughout human history, but in these modern times it gains potential for development.