The Better Buying Purchasing Practices Index (BBPPI) Methodology
The BBPPI uses a 0 to 100 point scoring system to calculate overall scores and scores for each purchasing practices category, with a larger number indicating better purchasing practices.
After scoring each question and category with a proprietary scoring methodology, the star “grading” is applied to the scores. The table below shows how stars are awarded to buyers, both overall and by category, according to the scores achieved by that buyer.
The same “grading standards” are applied to each category score, and to the overall weighted score.
Not all categories are weighted equally. The table below shows the weighting distribution for each purchasing practices category as a percentage of the overall score for each buyer.
The Better Buying Partnership Index (BBPI) Methodology
The BBPI methodology is based on Net Promoter Scoring (NPS), a widely used market research metric to measure customer experience. The possible range of BBPI Score is from -100 to +100, with -100 being the lowest partnership score, and +100 the highest.
The BBPI defines 3 BBPI categories of buyer: True Partners, Collaborators, and Detractors. Suppliers score their buyer on a scale of 1-5 on 12 partnership performance questions, where 1 is “never”, and 5 is “all of the time.”. Each of the 12 questions track back to the BBI Five Principles of Responsible Purchasing: time; visibility; stability; fair financials, and; shared responsibility.
The percentage of responses scoring the buyer as a True Partner for each of the 12 questions is averaged across all the 12 questions to get a True Partner percentage for that buyer, with the same process being used to calculate Collaborator, and Detractor percentages.
The percentage of Detractors is subtracted from the percentage of True Partners to derive the overall BBPI Score, rounded to the nearest whole number.
The higher the percentage of responses scoring the buyer as a True Partner, the better will be the buyer’s BBPI Score. A BBPI Score closer to 100 means that the buyer’s work and use of time is efficient and non-duplicative; their partnerships with their suppliers are marked with fairness, risk-sharing, and a long-term focus. A negative BBPI score means that a higher percentage of responses scored the buyer as a Detractor as compared to a True Partner.
A BBPI Score closer to -100 means that the buyer’s practices reflect a primary focus on achieving their own objectives and margins (often at the expense of suppliers), and this prevents open dialogue and blinds Detractors to opportunities for shared benefit.
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Companies interested in subscribing for the BBPI or BBPPI should contact Leonie Abraham, Director of Business Development, Cascale Better Buying.
More on Better Buying
The Better Buying Partnership Index (BBPI) is a short, anonymous, subjective survey of the quality of buyer-supplier partnerships, consisting of 12 subjective questions, which opens for supplier ratings on October 1 2025.
The Better Buying Purchasing Practices Index is a detailed deep dive into a buyer company’s Tier 1 purchasing practices which opens for supplier ratings on April 1 2025.
Cascale’s acquisition of Better Buying tools and methodologies reflects our commitment to advancing responsible purchasing practices and promoting fair, accountable, and socially just supply chains.
