This paper reports the application of an evidential reasoning (ER) approach, to deal with the evaluation of a contractor, from among different fabrication options of aero-engine equipment. This is followed by a review of current evaluation practices, which begins by highlighting their limitations and then goes on to justify the use of an evidential reasoning approach. The evaluation model is discussed and techniques for articulating the original evaluation data are also explored. A hypothetical selection problem involving the evaluation of different fabrication options for aero-engine equipment is then examined using this approach. Given the role of small firms as sub-contractors, and the difficulties that they face in managing the pricing part of the marketing mix, which is heightened when tendering is involved, this paper has lessons that extend outside of the particular industry that forms the case study. The case study itself draws from the real life experience of actual defence contract assessors.