---
title: "Human-in-the-loop (HITL)"
description: "The oversight mode in which a person can intervene in every decision cycle of an AI system; in engineering terms, a gate that holds each consequential action until a named approver decides, logging…"
canonical: https://aigovernanceengineer.com/glossary/human-in-the-loop-hitl
author: "Jorge García Aibar"
license: "CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/)"
doi: https://doi.org/10.5281/zenodo.22956197
version: "0.5.0"
updated: 2026-09-25
---

# Human-in-the-loop (HITL)

The oversight mode in which a person can intervene in every decision cycle of an AI system [1]; in engineering terms, a gate that holds each consequential action until a named approver decides, logging approver, time to decide and override.

- Developed in: [ch. 05, Pattern: Human-in-the-loop Gate](https://aigovernanceengineer.com/bok/patterns#pattern-human-in-the-loop-gate); [ch. 11, From definition element to registry field](https://aigovernanceengineer.com/bok/ai-defined#from-definition-element-to-registry-field); [ch. 23, Human checkpoints and approval design](https://aigovernanceengineer.com/bok/governing-agents#human-checkpoints-and-approval-design)
- Chapters: [ch. 05, Patterns](https://aigovernanceengineer.com/bok/patterns) · [ch. 11, AI Defined](https://aigovernanceengineer.com/bok/ai-defined) · [ch. 23, AI Agents](https://aigovernanceengineer.com/bok/governing-agents)
- Contrast with: [Human-on-the-loop (HOTL)](https://aigovernanceengineer.com/glossary/human-on-the-loop-hotl)
- In the glossary chapter: https://aigovernanceengineer.com/bok/glossary#t-human-in-the-loop-hitl

## Commonly confused

- **Human-in-the-loop (HITL)** vs **Human-on-the-loop (HOTL)**: A person approves each consequential decision, against a person monitors and can stop the system HITL is evidenced by approval logs and override rates; HOTL by alerting and a tested stop path

## Sources

[1] Ethics Guidelines for Trustworthy AI (four ethical principles; seven requirements; human-in-the-loop, human-on-the-loop and human-in-command oversight). High-Level Expert Group on AI / European Commission. 2019-04-08. https://digital-strategy.ec.europa.eu/en/library/ethics-guidelines-trustworthy-ai (verified: primary)