Bringing people in says so much about you as a leader,” says Stone. “That’s probably more important than anything. You’ve got to be really, really thoughtful.”

Whom you choose and the process you use to make those choices send substantive signals about your standards, expectations, and management style. The signals are especially strong when you look outside the company for candidates.

Words aren’t the only indicators of an organization’s culture. Superficial though it may sound, clothes also send some of the most obvious signals. For example, when Jim McNerney became CEO of 3M, starched shirts still prevailed at the top, while most of the employees dressed in workplace causal. For McNerney, the formal attire was a clue of the disconnection between management and the rest of the organization.

The bottom line is that in order to minimize your risk, you need to really familiarize yourself with the subtleties and idiosyncrasies of the culture, understand the power bases, recognize that a mandate from above may not automatically ensure a mandate from below, and not try to change the world in your first hundred days. Patience is often an essential virtue when it comes to cultural transformation at a large scale.

Creating the conditions for a cultural transformation takes all the tools at your disposal. You can’t, for example, command an internally focused culture to magically metamorphose into one that canonizes its customers. You have to nudge, suggest, cajole, and ultimately convince people that the new environment you’re proposing really is the best one for the business and, perhaps more important, for themselves. That takes time - and a good sense of timing.

Some leaders look back on their first hundred days and say, “If I could do it again, I wouldn’t hesitate so long to make those key people changes or that strategic move.” Others were glad they exercised restraint. In most cases the timing are dependent on the situation.

Communication is a central aspect of leadership and indeed all human activity. It has a magnified effect during your first hundred days. Take care to do it well and do it often, which requires active listening, tailoring communication approaches both to your natural strengths and to the situation, and giving and getting direct feedback. It will help support your strategic and cultural agenda; it will also help you avoid many of the most common pitfalls that threaten new leaders as they try to get off to the right start.