There are countless ways to commit bioviolence. Bioweapons are not a single, undifferentiated set of devices all used to common effect. Choices can be made from a lengthy menu of pathogens and a longer menu of dissemination methods to create many combinations; each faces different obstacles and has different consequences. Decades ago, there were only a few ways to commit a biocatastrophe, but bioscience progress is reconfiguring and rapidly expanding options.

How hard is it to commit bioviolence and how much specialized knowledge is needed? Much depends on the perpetrator's objective, the available pathogens and equipment, his organization's technical skill and sophistication, the risks of detection, and how those risks could be avoided. His choices in turn affect our tactics to defeat him. The essence of bioviolence prevention strategies is to make the hurdles of committing bioviolence more arduous; the bio-offender's challenge is to surmount or outwit those hurdles. This perpetual threat-response dynamic is one reason why bioviolence poses unique threats.

It is widely reported that bioviolence is easy, but even well-funded State programs have stumbled trying to make effective bioweapons. If it is that easy, why has there not yet been a successful catastrophic attack? Perhaps because it is actually more complicated. Many pathogens are ubiquitous and easily propagated; critical challenges tend to be about how to disseminate them either by physically spreading them amidst the target or by contagion. Yet, modern genomics is opening gateways for novel pathogens, and innovative engineering makes them easier to disseminate.