The current defense team confronted a game-changing "strategic shock" in its first 8 months in office. The next team would be well-advised to expect the same. Defense-relevant strategic shocks jolt convention to such an extent that they force sudden, unanticipated change in the Department of Defense's (DoD) perceptions about threat, vulnerability, and strategic response. Their unanticipated onset forces the entire defense enterprise to reorient and restructure institutions, employ capabilities in unexpected ways, and confront challenges that are fundamentally different than those routinely considered in defense calculations. The likeliest and most dangerous future shocks will be unconventional. They will not emerge from thunderbolt advances in an opponent's military capabilities. Rather, they will manifest themselves in ways far outside established defense convention. Most will be nonmilitary in origin and character, and not, by definition, defense-specific events conducive to the conventional employment of the DoD enterprise. They will rise from an analytical no man's land separating well-considered, stock and trade defense contingencies and pure defense speculation. Their origin is most likely to be in irregular, catastrophic, and hybrid threats of "purpose" (emerging from hostile design) or threats of "context" (emerging in the absence of hostile purpose or design). Of the two, the latter is both the least understood and the most dangerous. Thoughtful evaluation of defense-relevant strategic shocks and their deliberate integration into DoD strategy and planning is a key check against excessive convention. Further, it underwrites DoD relevance and resilience. Prior anticipation of September 11, 2001 (9/11) or the Iraq insurgency, for example, might have limited the scope and impact of the shock. In both instances, wrenching periods of post-event self-examination did help solve our current or last problem. They may not have been as effective in solving our next one. DoD is now doing valuable work on strategic shocks. This work must endure and mature through the upcoming political transition. The next defense team should scan the myriad waypoints and end points along dangerous trend lines, as well as the prospect for sudden, discontinuous breaks in trends altogether to identify the next shock or shocks. Doing so is a prudent hedge against an uncertain and dangerous future.