Imagine this: every month your company pays a bill for “cleaning services” to a vendor named SparkleClean. The invoices look real, the amounts are modest, and the payments flow through the accounts payable department without a second glance. The only problem? SparkleClean doesn’t exist. It’s a shell company created by a trusted employee, and the money goes straight into their pocket. This kind of fraud—messing with the buying and payment system—costs businesses billions every year, and it happens far more often than most people think. In this chapter we’ll look at how these schemes work, why they’re so tempting, and what makes them hard to catch.