We believe brands should keep the promises they make and ensure they deliver for their customers by meeting or exceeding their expectations. Promise has a range of co-creation processes that are designed to close the gap between customer expectations of brands and their actual experiences.
The Promise Index is a simple diagnostic tool to measure the gap between your brand's image - the key determinant of expectations - and customer experience. Produced with the London School of Economics (LSE), the Index gauges the relationship between brands and their customers. It sits in the co-creation space, mediates between brands and customers, and brings the two together.

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The Index surveys 3000 customers on the image/perception they have of over 160 brands (the image score) and the quality of the experience they got from using the product (experience score). Together, these two make up a brand's Index score which we use to form our Promise Index League Table.
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The Promise Gap measures the difference between customers' expectations of brands and the actual experiences they have when using them. It quantifies and reveals, in the format of index numbers, which companies most commonly exceed or fail to meet customer expectations and how this varies across different sectors. In other words, the Promise Gap measures which brands keep their promises.
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Statistical analysis carried out in conjunction with the LSE has shown that Promise Gaps are positively correlated with revenue growth. In 2006, revenues of brands with positive Promise Gaps grew at an average of 10.5%. Those with no significant gap grew at a moderate 4.1% and companies with negative gaps grew at a significantly lower 2.8%.
This link with revenue growth is solid evidence that Promise Gaps need to be managed. Ensuring the quality of consumer experiences while managing your brand's image and perception is one of the surest ways to outperform the market. Inevitably, it is a business skill that will become more important in the coming years.
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2008 INDEX NOW ONLINE
see link below
Here is our 2008 top-10 list of performing brands. As well as predicting future revenue growth and customer advocacy, this year’s Promise Index has unearthed fascinating insights:
1) In good times and bad, it is innovation, not marketing spend, that separates winners from losers
2) Customer experience is what fuels revenue growth and advocacy
3) Brands are more downwardly than upwardly mobile
4) Is “the writing on the wall” for domestic UK brands?
5) Brands need to stay close to where their competition is coming from
Download the full Promise Index 2008 article.
| Top Performers | Image | Experience |
|---|---|---|
| 8.11 | 8.08 | |
| Amazon | 7.71 | 7.71 |
| Singapore Airlines | 7.42 | 7.72 |
| Honda | 7.52 | 7.60 |
| Paypal | 7.83 | 7.29 |
| VW | 7.68 | 7.32 |
| Sony | 7.63 | 7.26 |
| Emirates | 7.38 | 7.43 |
| Asda | 7.23 | 7.52 |
| Virgin Atlantic | 7.12 | 7.58 |
We would be delighted to share our findings with you and explain how the Promise Index predicts how your brand will grow. Please contact Adrian Li for more information.

