D3 started in Cardiff in September 2019, while its founder was recovering from spinal surgery.
Kate Horsington had spent years running paid search for other people. A rock climbing accident, and the spinal fusion that followed, took her out of a normal working week for months. Recovery gave her time to think about what an agency would look like if it were built from scratch: small, senior, and honest about what the numbers can and cannot show. She set the company up while she was still recovering. She is fully recovered now, and the company has grown with her.
What the name means
Data Driven Decisions. The last word is the point. Data on its own is a cost. A dashboard on its own is a cost. The only thing that pays is a decision made better than it would have been without the work: which campaign to scale, which test to stop, which budget to move.
How that shows up
- We measure before we spend. Tracking is checked before the first budget change, because the platforms learn from whatever signal they are given.
- A test ends in a decision. Before a test starts, we write down which result would change what we do.
- We report the uncertainty. A range shows how far to trust a number and what it would cost to be wrong.
- A person stays in charge of the automation. Scripts and models do the repetitive work, with a log and an off switch.
Since then
Updated October 2026. The method has won seven categories at the European Search Awards: one in 2022, one in 2023 and five in 2025, including Best Use of AI in PPC. The full record is on the awards page.
If you are weighing up an agency
Ask how they would know whether their work was working. If the answer is a dashboard, keep looking. If you want a rapid evidence review of your accounts, get in touch.