A neck measurement device (20) and a method of selecting a pillow (1, 41, 51) which takes into account the physique of the user are disclosed. A neck compression index (NCi) is calculated being the weight of the sleeper in kilograms divided by the shoulder width (ear to outer arm dimension) of the sleeper in centimeters. Preferably a compensated NCi is calculated which takes into account the softness or hardness of the mattress. A pillow resiliency is then selected based on the (compensated) NCi. Color coded pillow slips can be used to assist sleepers to self-select a pillow appropriate for their physique. Mail order and Internet based selling methods are disclosed.