Measuring the effects of advertising above and below the line depends in my opinion mainly on having really exact data, and this market research finds very difficult. In theory, there are plenty of logical conceptions about how advertising ought to work, something like S-curves or other curves, but unfortunately there is so far scarcely any TRUE evidence to bear this out. Here I should like to throw a little philosophy into the discussion. The process by which theme advertising leads, we hope, to a visible success in promotion sales takes longer and operates at a deeper level than any price-off scheme. Judging the efficiency of advertising above the line by looking at short-term volume differences is very questionable unless the effects shown are positive but - and this is my question - does this mean that advertising has no effect whenever the effects are not so immediately perceptible?