Seeing as Dave Langford has won about a million Hugo Awards1, it may be stretching it a bit to say he's underappreciated. However, most of those Hugos have been for his (excellent) fan writing and his (excellent) newsletter Ansible: only one (for the title story of this collection) is for fiction, and, it seems to me, if this ratio was reversed that would be entirely justified, since Langford is, I think, One Of The The Three Best SF Short Story Writers Ever, Along With J. G. Ballard and John Sladek.
Despite the colossally cumbersome formulation above, that still might be thought a bold statement, but, to nick a title from John Clute, "look at the evidence": in this case, the book above, which collects much of Langford's serious sf from 1975 to 2003.
That word "serious" is possibly relevant. Langford is (rightly) highly regarded for his comic writing, and the wit of his remarkably long-running (and free) newsletter Ansible; and although there is (at least) one laugh out loud moment2 in the volume currently under advisement (in my case, his contribution to The Thackery T. Lambshead Pocket Guide to Eccentric and Discretited Diseases, "Logrolling Ephesus", the contributor's biography to which begins, "Dr. David Langford had the good fortune to commit his researches at a period when relevant legislation had yet to be urgently passed"), he is also, I'd aver, a more or less peerless exponent of the straight sf story.
The most famous examples here are the tales that make up the influential BLIT sequence ("BLIT", "What Happened and Cambridge IV", "comp.basilisk FAQ", and the Hugo winning "Different Kinds of Darkness"), which, via maths, terrorism, genuinely haunting and disturbing images, and pertinent points about information and childhood, detail the implications of a scary sf idea in a combined length of (think on this, fatnasty fans!) 28 pages...
Equally, "Waiting for the Iron Age", in just 4 pages (think on this fatnasty fans! -- you've done this -- Ed) sorts out the Wandering Jew legend in double quick time, whilst, as Langford says in his afterword, giving, "our man a longer run for his money than anyone else..."
Another thing with reviewing Langford, of course, touched on above, is his encyclopaedic knowledge of the sf world: if one were to, as one might, try to comment on the "The Motivation", by 'cleverly' mentioning the Christopher Priest-like nature of the title, and then try and draw a parallel with Priest's (very different) story "The Watched", one would find, on reaching the end of Langford's (excellent) story, that he's already there in his (as is typical in this collection) informative and splendid afterword. Heigh ho...
And what great titles, though! ("In A Land of Sand and Ruin and Gold"; "Blossoms That Coil and Decay"; "The Lions in the Desert" etc.)
Seriously, everyone should have this....
1 An exageration. Just!
2 I mean here the genuine laugh-out-loud moments that render you actually unable to speak even when reading alone, rather than as a shorthand for "quite funny". For more of these, see He Do The Time Police In Different Voices.