---
title: "Theory of Planned Behaviour (Ajzen) — Definition & Meaning"
description: "The Theory of Planned Behaviour predicts actions based on intentions shaped by attitudes and norms, crucial for UPSC GS4 ethics and decision-making."
url: "https://modeldiplomat.com/learn/glossary/theory-of-planned-behaviour"
---

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Model Diplomat Research Team · Last reviewed June 22, 2026

TL;DR

- The Theory of Planned Behaviour holds that a person's behaviour is predicted by their intention, which is shaped by attitude, subjective norms, and perceived behavioural control.
- How does the Theory of Planned Behaviour differ from the Theory of Reasoned Action?
- What are the three determinants of intention in the model?
- What is the intention-behaviour gap and why does it matter?
- Why is the theory relevant to UPSC GS4 ethics preparation?

[Civil Service & Diplomatic Exams](https://modeldiplomat.com/learn/civil-services/glossary)Updated June 22, 2026

The Theory of Planned Behaviour holds that a person's behaviour is predicted by their intention, which is shaped by attitude, subjective norms, and perceived behavioural control.

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