Reflections on an Icon Development Process: Managing Design 
Software organizations are increasingly willing to hire consultants in technical communication for projects in visual design. This paper examines ten factors critical to successfully managing icon development, based on experience in two different companies, Practical issues -defining the scope of the problem, recruiting the contractor and reviewers, writing the contract, deciding where the contractor should work, validating the images -- require attention to make your partnership with a consultant work.
Gould, Emilie W. STC Proceedings (1996). Articles>Graphic Design>Programming