Start with the outcome, not the fragrance
Before anyone smells anything, write down what the space is supposed to do. Extend dwell time. Lower anxiety. Feel more expensive. Feel cleaner. Feel like the brand rather than like a building. These objectives point to different fragrance families, and they occasionally conflict — a scent optimised for calm is rarely the one optimised for browsing.
A brief that says 'something fresh' produces the fragrance everyone forgets. A brief that says 'reduce the clinical association in the waiting area for an older patient group' produces a decision you can actually test.
Never select on a blotter
A blotter tells you what a composition smells like at full concentration, six inches from your face, for thirty seconds. It tells you nothing about how it behaves at 1,200 cubic metres, under air conditioning, after ninety minutes of continuous exposure.
Fragrances that are captivating on paper are frequently exhausting in a room, and the reverse is also true — several of the most successful commercial scents are unremarkable on a strip. Shortlist on blotters if you like, but decide in the space, with a trial unit, over at least a week.
Account for olfactory fatigue
Your nose stops registering a constant stimulus within minutes. Staff who work in the space all day will stop perceiving the fragrance entirely and will consistently tell you it has stopped working. Guests arriving from outside will perceive it at full strength.
This is the single most common reason intensity gets turned up until a space becomes unpleasant. Calibrate to the arriving visitor, not to the person who has been standing in it since nine in the morning, and use scheduled intensity rather than a constant level.
Decide by committee, but only at the end
One person's fragrance preference is not a brand decision. Shortlist to three directions internally, then trial them in sequence in the real space and gather reactions from people who do not know what is being tested.
The fragrance that wins is usually not anyone's personal favourite. It is the one nobody objected to and several people commented on unprompted.