I was reminded today about some of the classic Keith Laumer Retief of the CDT stories. To this reader's delight, at least some of them have been posted at Baen Books Online Library. And you can get at least one of the collections, Retief!, through Amazon.com.
For those unfamiliar with the series, it follows the career of Jame Retief, a (mostly) junior member of the CDT (Corps Diplomatique Terrestrienne), who is linguistically talented, physically gifted, intelligent, has little patience for fools, and rarely follows procedures to get the job done. For all these perceived faults, he does usually manage to succeed in whatever mission was asigned him, though his superiors do their best to deny him credit wherever possible (and in some cases promote those who do their best to work against their own Corps best interests).
As one of the reviewers noted, Retief took on PC (the dreaded Political Correctness) long before most people even realized it was a problem. Keith Laumer created one of the most memorable and believable heroes in the pantheon of science fiction. And he managed to do it with a nice mix of humor and adventure, maintaining his tone, something few other writers were able to master. Hat tip to the Instapundit.