The telephone number with the largest recognition worldwide is clearly 911. In fact, it's so well recognized and known, that it starts to create problems when it's used for non-emergencies.

Have we done too well of a job? Citizens know that 911 will reach public safety, but they don't stop to think they're tying up emergency dispatchers from real emergencies by calling 911. The problem is exacerbated when Public Safety officials can't agree on policy!