What Is Generative Engine Optimisation? How to Get Cited by AI Search

Generative engine optimisation is the practice of structuring your content so that AI answer engines, ChatGPT, Perplexity, Google AI Overviews, Gemini and Claude, quote and recommend it inside the answers they generate. Search is shifting from a list of ten blue links to a single synthesised answer, and if your brand is not in that answer, you are invisible to a fast-growing share of buyers. This guide explains what generative engine optimisation actually is, how AI search really chooses what to cite, and the concrete tactics that get your content pulled into AI answers.

It is written for marketers and store owners who can see AI search coming and want a plain-English plan, not jargon. At 5MS we are a UK eCommerce agency helping brands stay visible as search changes shape.

What Is Generative Engine Optimisation?

Generative engine optimisation, usually shortened to GEO, is the practice of structuring and publishing content so that generative AI answer engines cite it, quote it, or recommend it in the responses they produce. Where traditional SEO aims to rank a page in a list of results, GEO aims to make your content part of the AI’s answer itself. The term comes from a 2023 research paper that first framed optimisation for generative engines as a distinct discipline, and it has moved from academic idea to marketing priority as AI search has gone mainstream.

The mechanism underneath is retrieval-augmented generation (RAG). An AI engine breaks your page into passages, converts them into vectors, and retrieves the passages that are the closest semantic match to a user’s question before synthesising an answer and citing the sources it leaned on. That is why clarity, structure and self-contained claims matter far more for GEO than raw keyword density: the model is looking for the cleanest, most quotable passage that answers the question.

Why Generative Engine Optimisation Matters Now

More and more searches now end inside an AI answer. Google shows AI Overviews above the classic results, ChatGPT and Perplexity answer questions directly with citations, and a growing share of buyers research products and suppliers without ever clicking a traditional blue link. If AI is doing the summarising, the brands it cites win the attention, and the rest lose visibility they cannot easily win back with old tactics.

The uncomfortable part for anyone who has invested in SEO is that ranking well on Google does not guarantee you get cited by AI. Analyses of AI citations have found that fewer than 10% of the sources cited by tools like ChatGPT, Gemini and Copilot appear in the top 10 organic Google results for the same query. In other words, AI search visibility is a partly separate game, and treating generative engine optimisation as a bolt-on to SEO rather than a parallel discipline leaves citations on the table.

How AI Search Engines Actually Cite Sources

Each engine sources information a little differently, and understanding those differences shapes how you optimise. Two behaviours matter most. First, engines increasingly use fan-out: they break a question into smaller sub-queries, retrieve passages for each, and stitch the answer together, so content that covers the follow-up questions gets cited more. Second, they lean on trusted, well-structured sources, which is why authority and clean formatting punch above their weight.

That superscript citation is the whole game. Generative engine optimisation is the work that puts your domain in that Sources row.

The practical takeaway is that citations are fragmented: research across hundreds of millions of AI citations has found only around 11% of domains are cited by both ChatGPT and Perplexity. You cannot optimise for one engine and assume the rest follow, so GEO works best as broad, source-agnostic quality: clear answers, real authority and clean structure that any engine can trust.

Generative Engine Optimisation Tactics That Get You Cited

These are the practical moves that make content easy for an AI engine to retrieve, trust and quote. None of them is a trick; they are simply what clear, authoritative, well-structured content looks like.

Schema and Technical GEO

Structured data helps AI engines understand what your content is and how the entities on the page relate, which makes it easier to retrieve and trust. Schema is not a magic switch for citations, but it removes ambiguity, and less ambiguity means more confident use of your content.

Alongside schema, keep the technical basics right: fast, server-rendered pages, a clean site structure, accurate metadata and consistent entity naming. You can validate your markup with tools like Google’s structured data documentation and Schema.org. The same technical hygiene that helps SEO also underpins good generative engine optimisation.

Generative Engine Optimisation for eCommerce

GEO for eCommerce has a sharper edge than for content sites, because AI is increasingly where people compare products and shortlist suppliers. When a shopper asks an AI engine for the best option in your category, you want your brand and products in that answer. That means the same quality signals, applied to commercial pages.

This is also where GEO meets the wider shift toward AI-driven shopping. As agentic AI starts to browse and buy on shoppers’ behalf, being the source those agents trust becomes a commercial channel in its own right, a theme we cover in our guide to AI in eCommerce and our work on agentic commerce.

GEO vs SEO: Do You Still Need Both?

Yes, and they reinforce each other. SEO still drives the traditional organic traffic that converts, and a well-optimised, authoritative, technically sound site is also the foundation AI engines retrieve from. GEO does not replace SEO; it extends it to a new surface where the output is a cited answer rather than a ranked link.

The practical approach is to keep doing strong SEO, the technical health, the authority, the genuinely useful content, and then layer GEO habits on top: direct answers, quotable data, entity clarity, sub-question coverage and crawlability for AI bots. Because the overlap between what ranks and what gets cited is small, doing both is how you stay visible in classic search and in AI answers at the same time. Our eCommerce SEO work now builds GEO in from the start.

When to Use Generative Engine Optimisation Services

You can do a lot of GEO yourself, and much of it is simply good content practice. But generative engine optimisation services earn their keep when you need to move fast, measure AI visibility properly, and treat it as an ongoing programme rather than a one-off audit. Specialist help usually makes sense when you cannot see whether AI engines are citing you, when your content is not being picked up despite ranking well, or when you want GEO built into a wider SEO and content strategy rather than bolted on.

Good generative engine optimisation services do three things: audit your current AI visibility and crawlability, restructure and create content that engines want to cite, and track citations across ChatGPT, Perplexity, Google AI Overviews and the rest so you can prove progress. At 5MS we build this into our wider eCommerce services rather than selling it as a bolt-on. It is early, the tools are maturing, and the brands that start building AI search visibility now will have a real head start as this becomes mainstream.

Frequently Asked Questions

Common questions about generative engine optimisation. Get in touch if yours is not here.

Sources: GEO: Generative Engine Optimization (research paper), Search Engine Land GEO guide and Google structured data documentation. Citation stats are third-party estimates and this is a fast-moving field, verify before quoting.

By the 5MS team, UK eCommerce agency and Adobe Solution Partner. Last updated: August 2026.