This report is intended as a guide to assist in the development of a specification for analysers and their associated support systems for enquiry purposes and the subsequent assessment of the bids presented by the prospective vendors. This report is not intended as a design specification in its own right and design guidance has been deliberately omitted. It should be read in conjunction with other standards calling up examples of design detail, e.g. NAMUR, EEMUA, ISA. The technical report IEC/TR 61831, also being published, will supplement design guidance. To simplify the specification and bid process it is desirable to have a recommended procedure for both the enquiry documentation and the response from the analyser vendor. This document is intended to provide such a framework.