The US government warnings about tainted imports from China are ominous and ongoing. In July 2007 poisonous chemicals were found in toothpaste. This was just a month after imports of farm-raised Chinese seafood and lead paint in Thomas the Tank Engine toy trains were detained. And May had seen contaminated pet foods sicken and kill thousand of US cats and dogs. Now its humans, when earlier this month every parents' nightmare became a reality: Melamine contaminated infant formula poisoned more than 50,000 Chinese infants and resulted in at least four deaths.

While much government attention focuses on the problems in China, experts say the emergence of these deficient goods highlights the risks associated with today’s global supply chains. The far-flung networks of suppliers and transportation systems connecting them to their destinations present a new set of challenges.

Longer supply chains mean more participants, and with that, come bigger risks. “There are more people that companies need to watch and make sure they trust,” says Yossi Sheffi, professor of engineering at MIT and an expert in risk analysis and supply chain management. Supplier visibility is a problem for many organizations, according to Mark Hillman, a research director at AMR Research, who says many companies operating globally don’t know every player in their supply chain as well as they should. In addition, increased speed means decreased time for product checks. Goods rarely stagnate in warehouses, so there is less opportunity to conduct quality checks, says Sheffi.

Such threats to the supply chain increase the importance of security, which like any other type of risk management, can be a hard sell. Getting it in place can be costly, and ROI is hard to justify, unless, of course, something goes wrong. The key to selling security, experts say, is to emphasize the collateral benefits—the kind of ROI that will be realized regardless of disaster. A 2006 Stanford report, which studied the supply chain behaviors of 11 logistics companies that are considered innovators in supply chain security, outlines some of those benefits: improved efficiency, better customer satisfaction, better inventory management, and reduced cycle and shipping time. (See a copy of the study here.)

Below are some of the most common supply chain risks according to Sheffi and Hillman, and ways you can manage them through security, resilience and vigilance.