Imagine arriving at your new company knowing you're next in line for the CIO job. The succession plan is set, then suddenly the current CIO falls out of favor and leaves. The board decides to look outside for the new IT chief. You've been passed over. Not long ago, that unhappy scenario befell a friend of mine; she felt as though the company she had counted on pulled a bait and switch.

As our story ("The Replacements") notes, succession planning is a "long and difficult process with no guarantees." Robert Half Technology says that only 19% of CIOs do such planning. Gartner Inc. analysts weigh in to note that the probability your designated successor will get the job is quite low. In some cases, CIO successors tire of waiting and leave. But just as often, the designated IT drivers fail to win the confidence of senior management.