Table of contents
How Brands Grow: What Marketers Don’t Know is a 2010 book by Byron Sharp of the Ehrenberg-Bass Institute. It argues, from decades of buyer-behaviour data, that brands grow mainly by winning more buyers, not by making existing buyers more loyal. To win them, a brand must be easy to think of in buying situations (mental availability) and easy to find and buy (physical availability). This page is for B2B marketers who have heard “mental availability” in a meeting and want the substance, the B2B evidence, and the limits.
Correct as of 27 October 2026.
The core ideas in plain English
| Idea | What it says | What it means for your plan |
|---|---|---|
| Penetration over loyalty | Brands grow mainly by adding buyers | Spend on reaching people who do not buy from you yet |
| Availability | Buyers choose brands that are easy to think of and easy to find | Fix findability as well as awareness |
| Double jeopardy | Smaller brands have fewer buyers and lower loyalty | Loyalty follows size, so you rarely buy it on its own |
| Category entry points | The cues buyers use to retrieve a brand in a buying situation | Link your brand to many buying situations, not one |
| Distinctiveness | Brands compete on recognisable assets such as logos, characters and colours, not meaningful differentiation | Build distinctive assets and keep them consistent |
Peter Weinberg of the LinkedIn B2B Institute summarises the worldview in one line:
“Brands grow by acquiring new customers, NOT by increasing customer loyalty.”
Peter Weinberg, LinkedIn B2B Institute, in a LinkedIn post about the Ehrenberg-Bass research
Mental and physical availability
Mental availability is the likelihood that a brand comes to mind when someone is in a buying situation. Physical availability is how easily they can find and buy it. A brand needs both: one that is remembered but cannot be found loses the sale, and one that is easy to buy but never comes to mind is not considered.
The sequel, How Brands Grow Part 2 by Jenni Romaniuk and Byron Sharp, extends the theory. Romaniuk’s best-known contribution is category entry points: the cues, such as motives, emotions, location and time of day, that people use to retrieve a brand from memory when they face a buying situation, as Marketing Week describes them.
What it means for B2B marketing teams
The LinkedIn B2B Institute and the Ehrenberg-Bass Institute published How B2B Brands Grow, which tests the laws on B2B data. Four findings matter for planning:
- Acquisition drives growth. The double jeopardy law holds across B2C and B2B, so loyalty follows penetration.
- Most buyers are not buying now. The report includes John Dawes’s 95-5 rule, and Marketing Week ran a related piece under the headline “Ehrenberg-Bass: 95% of B2B buyers are not in the market for your products”.
- Aim for wider networks. Romaniuk says the aim is “wider, fresher networks”, with the brand “behind as many of those doors as possible”, which she contrasts with finding one thing to own, according to Marketing Week.
- Buying situations lift retention. In US insurance, each extra category entry point a customer linked to a brand lowered the chance of defection by 5%, according to Marketing Week’s report on the research.
“Category entry points are not about the brand, they’re about the buyer.”
Professor Jenni Romaniuk, Ehrenberg-Bass Institute, speaking to Marketing Week
Provenance matters here. The B2B Institute is a think tank supported by LinkedIn, which sells B2B advertising. The 5% figure comes from regression modelling across 17 products in the US insurance sector, as Marketing Week reports. Treat it as strong evidence for that sector and a hypothesis for yours.
The practical consequence is a shift in what you measure. Jon Lombardo of the B2B Institute makes the case against click-led thinking:
“It’s your memory that got you to Google in the first place and your memory is going to pull strong brands. Strong brands are not built on clicks, but on memories.”
Jon Lombardo, global head of research, LinkedIn B2B Institute, as reported by Marketing Week
Where the evidence runs thin
- B2B data is newer. The B2B Institute’s introduction describes its report as bringing the Ehrenberg-Bass ideas to the B2B world “with specific B2B data”. The double jeopardy law was first identified in the 1960s, and B2B tests came much later.
- Small addressable markets. Our view: if you sell to 400 target accounts, “reach every category buyer” is a short list, so account-based marketing and broad reach are not in conflict. The frameworks assume large markets.
- Measurement is harder than a survey. Mental availability is about buying situations, not general brand awareness. Measuring it takes dedicated research that links brands to specific buying situations (category entry points).
- It is not a budget rule. Sharp explains why broad reach matters, not how much to spend. For a split between brand and activation, read our summary of The Long and the Short of It.
How to apply it
- Audit physical availability. List where a buyer can find you: search, review sites, marketplaces, sales conversations. Fix the gaps first, because awareness without findability is wasted.
- List your category entry points. Write down the situations, motives and cues that make someone start looking, and note which ones your brand is already linked to.
- Choose distinctive assets and keep them consistent. The B2B Institute’s examples of distinctiveness are logos, characters and colours.
- Plan for reach, not just targeting. Keep brand activity always on and aimed at the whole category, alongside the demand capture in your channel mix.
- Run it as a measured campaign. Set a baseline for branded search, direct traffic and mental availability, launch, and compare. Our guide to brand, demand and expand shows how the pieces fit.
The bottom line
Sharp’s core claim is simple and testable: grow by reaching more buyers, be easy to remember, and be easy to buy. The B2B evidence is newer and partly vendor-sponsored, so use it to form hypotheses and test them on your own data. Pair it with our guides to the consumer decision journey and the Gartner B2B buying journey, and see the wider reading list in the best growth marketing books.
About Growth Method
Brand-building campaigns pay back slowly, which makes them the first thing cut when budgets tighten. Growth Method gives B2B marketing teams AI agents that run their campaigns: plan, launch and analyse, from live data, against one goal. A long-cycle brand campaign gets the same plan, launch and analyse loop as a short one, so you can judge it on a baseline rather than on last-click results.
We are on-track to deliver a 43% increase in inbound leads this year. There is no doubt the adoption of Growth Method is the primary driver behind these results.
Laura Perrott, Colt Technology Services
Get started and plan your first brand-building campaign with a baseline you can compare against.
Frequently asked questions
What is How Brands Grow about?
How Brands Grow is a 2010 book by Byron Sharp of the Ehrenberg-Bass Institute. It argues that brands grow mainly by winning more buyers, not by making existing buyers more loyal, and that they win buyers by being easy to think of (mental availability) and easy to find and buy (physical availability).
What are mental and physical availability?
Mental availability is the likelihood that a brand comes to mind when someone is in a buying situation. Physical availability is how easily they can find and buy it. A brand needs both, because a brand that is remembered but cannot be found loses the sale.
Does How Brands Grow apply to B2B?
Largely yes, according to research by the LinkedIn B2B Institute and the Ehrenberg-Bass Institute, which found that the double jeopardy law holds across B2C and B2B and that most B2B buyers are out of market at any given time. The B2B Institute is supported by LinkedIn, and some results, such as the effect of category entry points, come from a single sector (US insurance).
How is How Brands Grow different from The Long and the Short of It?
Binet and Field’s research gives you a budget split between brand building and short-term activation. Sharp’s work explains why broad reach and consistent distinctive assets matter. They broadly agree that sustained brand investment beats pure short-term activation, and many teams use both. Read our summary of The Long and the Short of It for the budget split.