Describe briefly the main stages included in the (rational) process of consumer behaviour when making a purchase. 

Problem/Need recognition

The purchasing process is a problem solving process of how to satisfy a requirement or want. Crucially consumers do not so much buy goods or services as satisfy a demand or need by the purchase. The first stage is that the consumer identifies that requirement or problem. 

Information searching

The second stage involves the consumer performing a search of several options to satisfy the identified need. This might be done informally through remembering past experience, talking to others or more formally by consulting directories, 'window shopping' alternatives or internet search engines. 

Evaluation of alternatives

This stage involves the consumer in comparing several brands and products in order that a choice might be made between the viable alternatives. 

Purchasing decision

Next the customer actually makes a purchase choice. The choice is only normally altered if (for instance) there is a temporary 'stock-out' or further information emerges about the alternatives which were rejected initially.