In addition to its precision superiority over nonadaptive tests, another known advantage of computerized adaptive tests (CATs) is that they can be offered on a continuous basis. This is advantageous to examinees in terms of flexibility of test scheduling, as well as advantageous to schools and other testing centers in terms of both space and number of computers required for testing. Unfortunately, it must be acknowledged that continuous testing capability is also the major weakness of CATs: Continuous testing implies continuous item exposure. Examinees who took tests earlier may share information with examinees who will take the tests later; there is a risk that many items may become known to examinees before the actual test dates. Chang and Zhang (2002, 2003) initiated the theoretical developments in assessing test security severities for high-stakes CATs. Their theoretical derivation is based on a randomization item selection procedure that provides equalized item exposure and, hence, the best test security control in CATs.