Science-Based Targets (SBTi) begin with a commitment letter and end with a validation approval. There are usually eighteen months in between — and how you plan that period determines whether the target is realistic.

The first step is a declaration of intent: you send a commitment letter to SBTi and formally enter "target-setting" status. At this point you don't yet have a number — you only have a timeline: you must submit the target within 24 months.

The real work is calculating the target. You choose a base year, establish your Scope 1, 2, and material Scope 3 emissions, and select a reduction trajectory appropriate for your sector. If Scope 3 data is weak, target-setting stalls here — which is why inventory work must come before target-setting.

The final phase is validation: you submit your target to SBTi, the technical team reviews it against the criteria, and approves it. The approved target is published and regular progress reporting begins.

Common mistake
Most teams send the commitment letter before the inventory is ready. The 24-month clock starts ticking, but there is no Scope 3 data. Solidify the inventory first, then commit.

— Zeynep, May 2026