“The True Measures of Success” by Michael J. Mauboussin in the Harvard Business Review this month is well worth a read for many things, not least of all is an anecdote:
What happened? We made a mistake that’s exceedingly common in business: We measured the wrong thing
The article is available here and while it is naturally focused on commercial business, many of the insights the article contains would add much to the attempts made in Public Diplomacy to measure success.