This paper argues that the reliability of engineering computation can be significantly improved by adopting software engineering methodologies for requirements analysis and specification. The argument centers around the fact that the only way to judge the reliability of a system is by comparison to a specification of the requirements. This paper also points to methods for documenting the requirements. In particular, a requirements template is proposed for specifying engineering computation software. To make the mathematical specification easily understandable by all stakeholders, the requirements documentation employs the technique of using tabular expressions. To clarify the presentation, this paper includes a case study of the documentation for a system for analyzing statically determinant beams.