What is Marketing Effectiveness?

The Definition

Marketing effectiveness is not the same as marketing efficiency. Efficiency is about doing things cheaply — low cost per click, low cost per acquisition. Effectiveness is about doing things that actually work — generating revenue, building brand equity, and growing market share in ways that compound over time. A campaign can be highly efficient and almost completely ineffective. A campaign can be relatively expensive and enormously effective.

Peter Field — who has worked with the IPA Databank for over two decades and is one of the most cited researchers in the field — defines effectiveness as the generation of profit-driving business outcomes through marketing. His benchmark is not return on ad spend or click-through rate but metrics that matter to a business: market share, pricing power, revenue growth, and customer acquisition cost over time.

Where the Evidence Comes From

The IPA Effectiveness Awards Databank is the most comprehensive database of advertising effectiveness evidence in the world. It contains thousands of case studies submitted by agencies and brand teams, each documenting the business outcomes of marketing campaigns. Peter Field and Les Binet have spent decades analysing this data and their findings — most notably in The Long and the Short of It — have become the foundation of modern effectiveness thinking.

James Hurman — founder of Previously Unavailable and one of the most rigorous researchers into creative effectiveness — has extended this work to show the relationship between creative quality and business results. His analysis of creatively awarded campaigns versus non-awarded campaigns shows that the former significantly outperform the latter on every business metric in the IPA data. Creativity and effectiveness, it turns out, are not in tension — they are causally linked.

Short-Term vs Long-Term Effects

One of the most important findings from the IPA data is that marketing effects operate on two distinct timescales that require different types of activity. Short-term activation campaigns — direct response, promotions, performance marketing — generate immediate sales by capturing demand that already exists. These effects are strong and fast but decay quickly when the campaign ends.

Long-term brand campaigns work differently. They build mental availability — the probability that a brand comes to mind when a buying situation arises — and distinctive brand assets that trigger recognition. These effects are slow to build but persistent, and they compound over years. A brand that has invested consistently in brand advertising for five years is significantly more resilient to competitive pressure and economic shocks than one that has not, even if the short-term sales effects look identical.

Tom Roach — VP Brand Strategy at Jellyfish — describes the relationship as brand activity creating a reservoir of demand that performance activity then harvests. Without the reservoir, performance marketing has less to draw from.

Why It Is Hard to Measure

The central challenge of marketing effectiveness is that the most important effects are the hardest to measure. Short-term activation is easy to track — last-click attribution, return on ad spend, conversion rates all give clear signals within days or weeks. Long-term brand effects play out over months and years, and their contribution to a sale that happens eighteen months from now is almost invisible to standard measurement tools.

Grace Kite — founder of Magic Numbers and one of the most respected econometricians working in marketing — has spent her career building models that make long-term effects visible. Her approach uses econometric modelling to decompose revenue into its contributing factors — media, promotions, distribution, economic context, and brand — and quantify the contribution of brand investment over time. This gives marketers a defensible number to bring to the CFO rather than an argument about intangibles.

The Share of Voice Principle

One of the most robust and actionable findings in effectiveness research is the relationship between share of voice and share of market. Brands that maintain a share of advertising voice above their current share of market tend to grow. Brands that fall below tend to decline. Peter Field has referenced this finding — originally documented by the late Andrew Ehrenberg — repeatedly as the most useful single indicator of whether a brand is investing enough. It does not require sophisticated modelling. It requires knowing your competitive spending environment and your current market position.