In this chapter, we start by introducing Cloud Computing management terms, with a special reference to Amazon Web Services (AWSs). Next, we review the performance characteristics of public, multi-tenanted data centers, including the concept of noisy neighbors. If a particular VM does excessive I/O or memory accesses, then other VMs running on that same server will experience a slowdown in their access of the same physical resource. This results in a performance variation experienced by a VM user over time. Such factors impact run-times of users’ applications and result in different cost to finish a task. A cloud user may want to maximize their performance or minimize their costs. We will look at various monitoring tools, to manage the user costs.