---
title: What is Decision layer?
url: https://markin.ai/glossary/decision-layer
category: Markin vocabulary
aliases: Decisioning layer
---

# Decision layer

> A decision layer is the system that sits between the data warehouse and the execution tools and decides, per customer, what deserves to happen next. It does not store the data and does not send the message; it owns eligibility, arbitration, timing, measurement and the record of why each decision was made.

## Why it matters for ARPU

Warehouses answer what happened and engagement platforms answer how to send. Neither decides what is worth doing, which is where most of the recoverable ARPU sits.

## Related terms

- [Customer data platform](https://markin.ai/glossary/customer-data-platform), A customer data platform collects customer data from multiple sources, resolves it to unified profiles and makes segments available to downstream tools.
- [Next best action](https://markin.ai/glossary/next-best-action), Next best action is the single intervention that maximises expected value for a specific customer at a specific moment, chosen across every available option including doing nothing.
- [Arbitration](https://markin.ai/glossary/arbitration), Arbitration is the step that resolves competing candidate actions for the same customer into one decision, ranking them by expected value under constraints such as contact limits, budget, fairness and business priority.
- [Real-time decisioning](https://markin.ai/glossary/real-time-decisioning), Real-time decisioning evaluates a customer's current context and returns an action within the latency budget of the moment, typically tens of milliseconds inside an app or call.

## Go deeper

- [Data warehouse vs CDP vs decision layer](https://markin.ai/compare/data-warehouse-vs-cdp-vs-decision-layer), Where each system starts and stops.
- [Markin product](https://markin.ai/product), The layer, end to end.

Source: https://markin.ai/glossary/decision-layer