Solomon Leseriani - very highly recommended, with very reasonable fees
Lazaro Aloyce - also very highly recommended; 
Machame @ 2980M (night 1)
Shira Camp @ 3760M (night 2)
Lava Tower @ 4630M (night 3)
Arrow Glacier @4800M (night 4)
Crater @5700M (night 5)
Mweka camp 3100M (night 6)
the rainforest
the moorland
climbing the lava tower
sunrise over kili from the top of the lava tower
ascending arrow glacier - very scary
rock climbing up Western Breach
simultaneous sunset and full moon rise over the crater - July 13, 2003
staying in the crater
visiting the ash pit
(As far as I can tell, every single person in the city of Arusha has a relative or friend who 
is a kili guide.  Make sure you have a bona fide recommendation.)
There also seem to be a fairly unlimited number of travel companies offering climbs.  
Many of these are very reputable companies, 
although I have no direct basis for recommending any of them.
In general they use local guides and porters.
Here is a sample:
Students for International Change (SIC)
      
Modified: June 12, 2015
Created: March 27, 2003
contact: siegelr@stanford.edu
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