This document outlines a five stage model of consumer decision making: 1) need recognition triggered by internal or external stimuli, 2) information search through heightened attention or active searching from various sources, 3) evaluation of alternatives using expectancy value models and considering brand beliefs and importance of attributes, 4) purchase decision using heuristics like conjunctive or lexicographic rules, 5) post-purchase behavior and evaluation. The model seeks to explain how consumers identify needs, gather information, and make purchase decisions.