Check out Samification

Get Between the Spreadsheets

Sign up to our Monthly Newsletter

About Us
The data quality experts

The Classification Guru provides expert data classification, data cleansing, and data normalisation services to organisations worldwide. Founded in 2017, we have over 30 years of combined experience and have supported more than 100 organisations in improving data quality across procurement, finance, sales, and marketing systems, in multiple languages and regions.

Our specialist team applies the COAT framework to ensure data is consistent, organised, accurate, and trustworthy. We work with supplier data, spend data, CRM and ERP data, identifying errors, duplicates, and inconsistencies that undermine reporting, analytics, AI, and decision-making.

We also deliver data diagnostics and database cleansing services, giving organisations a clear view of data quality before system implementations such as CRM, ERP, or P2P, and a practical roadmap to fix issues quickly and sustainably.

We help you:

✔ Improve data quality through accurate data classification and cleansing

✔ Create reliable, decision-ready data for reporting, analytics, and AI

✔ Reduce risk, save time, and improve operational efficiency

Find out more about our services
What makes us different

We are human-led data classification and data cleansing specialists, combining expert judgement with specialist software and our proven COAT framework. Our work gives you confidence that your data is consistent, organised, accurate, and trustworthy – the foundations that AI, analytics, and automation need to work effectively.

We don’t just deliver clean, decision-ready datasets. We also create high-quality, validated training data to support future AI and automated classification initiatives. We fix your structure, standards, and classification upfront, so you can reduce risk, improve AI performance and stop automating poor-quality data.

Read more about how we work
The Classification Guru and AI

 

AI isn’t a threat to what we do; it relies on it. Machine learning and automation are only as good as the data they’re trained on –  poor-quality data creates faster, more confident errors.

Our work complements AI by providing clean, accurate, and consistently classified datasets suitable for training data. By fixing data quality first, we help organisations introduce automation and AI more confidently, avoiding the risk of scaling dirty data. If you’d like to explore this further, read our blog where we share our thinking on AI, automation and data classification.

Learn more about data classification and automation
Meet the original Classification Guru

Susan Walsh is a globally recognised expert in data classification, taxonomy design, and data cleansing, and the creator of the COAT framework, the methodology that underpins all of our work. With over a decade of hands-on experience fixing dirty data, Susan helps organisations turn inconsistent, unreliable data into structured, trustworthy information they can confidently use for reporting, analytics, and AI.

Susan founded The Classification Guru in 2017 and has since supported more than 100 organisations worldwide across procurement, finance, sales, and marketing. Known for bringing clarity to complex data problems, she helps teams work more efficiently, reduce risk, and make better business decisions by fixing the data at its source.

An established industry thought leader, Susan is a TEDx speaker and the author of two books: Between the Spreadsheets: Classifying and Fixing Dirty Data, and Optimizing Sales and Marketing Data. She speaks globally at leading events including ProcureCon, Big Data LDN, and Big Data & AI World, where she’s known for cutting through jargon and explaining data quality in a practical, engaging, and refreshingly honest way.

Connect with Susan on social media to follow her work, insights, and straight-talking views on data, governance, and AI.

Read Susan's book Between The Spreadsheets

Between the Spreadsheets: Classifying and Fixing Dirty Data
covers everything from data classification, normalisation, and taxonomy design, Between the Spreadsheets shows how the COAT framework helps organisations create consistent, trustworthy data.

Learn more about Between the Spreadsheets

Susan helped us tremendously to normalize and classify our spend for the first time

We started our spend classification project with Classification Guru, because we had disparate back-end systems and no consistency or visibility into our spend. Susan was wonderful to work with, because she had a lot of patience to work through information from many sources and in many languages. She helped us tremendously to normalize and classify our spend for the first time. We had quite a few edits and revisions and she was very attentive and fast getting them done. Today we have a much better understanding of our spend in the different regions where we operate and her help at making sense of the data was invaluable to us.

Alan Rice
Global Procurement

Working with Susan has been a breath of fresh air

Working with Susan has been a breath of fresh air. Her insights on how to tackle the up-front cleansing and ongoing maintenance of our external third party supplier spend data has helped us to completely reset the way we approach business compliance conversations with our internal colleagues. We now have accurate, timely data feeding into monthly spend dashboards and compliance reports that the business trusts and uses to drive behaviour change. What has impressed me the most about The Classification Guru team is that they don’t just present a theoretical vision on powerpoint, they actually understand and do the work themselves, and then go over and beyond to make sure you have a sustainable solution in place after they leave. And all with big smiles and fun along the way. Highly recommended!

Procurement Enablement Director
Consumer Insights Business

I have no idea how Susan managed to accurately classify so much data in such a short period of time

We found the Classification Guru while looking to establish a brand new global indirect procurement function, and having found our GL code usage to have been too inconsistently applied to be useful for classification purposes.

Working with Susan was very straightforward, and with her help we were able to classify around 95% of our several thousand global suppliers within just a few weeks, with a high level of accuracy, and at a very reasonable overall cost. This was invaluable in allowing us to develop our spend analytics very early in our project.  I have no idea how Susan managed to accurately classify so much data in such a short period of time, but I would have no hesitation in recommending her services to anyone in the same situation.

Simon Pett
Varian Medical Systems Inc.

We are now set up for success for our implementation of a new spend analytic tool.

We are set ourselves the challenge of standardising our spend taxonomy and made the decision to use the taxonomy that more than one site was using, as the starting point. What Susan then helped us to do in bring the outside in, to make sure we had not missed any spend areas and we had find the right balance between granularity and a user friendly taxonomy. Susan made some good suggestions on improvements we could make and what was impressive was how quickly she was able to turn this around, particularly due to the amount of data we provided her with, the different languages it included and the different formats. We are now set up for success for our implementation of a new spend analytic tool.

Twinings
OVO

Get in Touch

For more information about our services or how we work, contact us using the form below.

I'm Interested In: