The old stores, still worth opening.
Explore Principles
The handful of ideas most marketing still rests on, each with the person and the year it came from.
The 4 Ps of marketing
The marketing mix says a marketer's job is to set four controllable variables: product, price, place and promotion. It is a classification, not a theory, and has never been tested as one.
Positioning in marketing
Positioning, as Ries and Trout set it out in 1972, claims that a brand wins by occupying one clear slot in the prospect's memory. The memory half holds up.
Market segmentation
Market segmentation claims a market is not one demand curve but several, and that a firm does better serving some of them well than all of them adequately. The evidence supports that claim for categories: buyers differ in what they want and how much they use.
Unique selling proposition (USP)
Rosser Reeves set out the unique selling proposition in 1961 as a three-part rule: every advertisement must offer a specific benefit, competitors must not claim it, and it must be strong enough to pull new buyers. His evidence was agency data.
Mental availability and physical availability
Sharp's claim is that brands grow by being easy to think of and easy to buy, because loyalty follows market share rather than causing it. The second half is well tested: double jeopardy holds in 32 differentiated replications, in cars, business banking, aircraft and packaged goods.
The Long and the Short of It
Binet and Field claim that advertising works in two modes on two clocks: activation sells now and fades, brand building sells later and compounds, so budgets should lean long, at roughly 60:40. The evidence is 996 award entries in which volume arrives within months, pricing power takes years, and efficiency peaks at 30 to 50 percent activation.
AIDA
AIDA claims that a buyer passes through attention, interest, desire and action in that order, and that a message should push them along it. The attribution to E. St. Elmo Lewis in 1898 rests on one uncited sentence in a 1925 textbook; the four steps first appear in salesmanship magazines of 1903 and 1904 under other names.
Brand equity
Brand equity is the claim that a name adds value beyond what the product does, and that this value can be built, measured and banked. Aaker (1991) listed the assets; Keller (1993) located them in the customer's memory.