To buying organisation, savings can be achieved from different saving levers or tactics. Which of the following are means that deliver savings through optimising specifications?

Optimising specifications is a technical savings lever focused on changing the design, material, or functional requirements of a purchased item to reduce costs. Value engineering (A) is a systematic method to improve the "value" of goods by examining function and cost, often leading to specification changes. Part substitution (B) involves replacing a specified component with a lower-cost alternative that performs the same function, which is a direct change to the bill of materials or specification. Both tactics directly address the technical makeup of a product to achieve savings, rather than focusing on commercial terms or processes.

C. Budget linkages are an internal financial control process, not a method for changing product specifications to generate savings.
D. Comparing the total cost of ownership (TCO) is an analysis technique used to evaluate options, not a tactic to change specifications itself.
E. Volume pooling is a commercial lever that achieves savings through economies of scale by aggregating demand, not by changing specifications.

CIPS (2018), Defining Business Need L4M2, Stamford: Profex Publishing, pp. 119-121. This module discusses value analysis and value engineering as key tools for challenging and optimising specifications.

Van Weele, A. J. (2018). Purchasing and Supply Chain Management (7th ed.). Cengage Learning. Chapter 11 discusses purchasing and product strategy, including value engineering and standardisation as ways to influence specifications for cost reduction.

Monczka, R. M., Handfield, R. B., Giunipero, L. C., & Patterson, J. L. (2016). Purchasing and Supply Chain Management (6th ed.). Cengage Learning. Chapter 8 covers value analysis/value engineering and standardisation as key cost reduction strategies related to specifications.