This paper details an alternate methodology that permits the consumer decision process to be observed without the constraint of model phases or 'sets'. A new custom-developed computerised process tracing methodology is utilised, identifying the decision wave boundaries in a durable product purchase scenario. The electronic process tracing methodology reveals multiple pathways to consumer choice for a durable purchase decision. Consumers choose an air-conditioning alternative using up to ten decision waves, 40% of which may be outside our current decision models. This research suggests that most consumers do not construct a choice set to make a purchase decision, and this may have an impact on product positioning and differentiation decisions, as well as identifying the importance of being the 'last alternative standing'. This research found three common pathways to consumer choice. Marketing tactics must address the informational requirements of each pathway for their product to become a candidate for selection.