There are four key terms that are used by agencies in defining VfM (Economy, Efficiency, Effectiveness and Equity). Here is a definition of each term: 

• Value for money development should be economic: inputs have been procured at the least cost for the relevant level of quality. For example, in evaluating a training course being delivered in Australia the slightly higher costs for accommodation and flights may be justified given the experience that the cohort requires their own cooking facilities and that flights need to be flexible because participants often change and this leads to more cost in the long run.  
• Value for money development should be efficient: Efficiency is generally defined as considering the value of outputs in relation to the total cost of inputs (at the relevant level of quality). Some define efficiency as the value of outcomes in relation to the total cost of inputs. To take the more often used definition, in an education evaluation the costs of developing a curriculum (including the costs of the curriculum specialists, graphics designers, and delivery) may be considered not worth the cost due to the cultural mismatch of the content produced. 
• Value for money development should be effective: achieving program outcomes in relation to the total cost of inputs (sometimes equity considerations are factored in here). For example, a advocacy program that worked with landless migrants may be highly effective because it achieved shared land title for the community. The advocacy campaigners worked in concert with local advocates – so the inputs were strategic and limited keeping the costs down.  
• Value for money development should be equitable: ensuring that benefits are distributed fairly. For example, a small business incentive program that did not reach the most remote and vulnerable parts of the population may be evaluated as inequitable. 

It is important to note that not all agencies use all terms. DFID, for example, uses the first three Es. The Independent Commission for Aid Impact adds the fourth dimension. In addition, they suggest balancing the four elements. So there are questions for each evaluator and each agency about what your definition of VfM will be and how you will come to a VfM judgement. And it is important to bear in mind these key terms.