Experts believe that firms embarking on email marketing for the first time can drastically improve their ROI by targeting clients in terms of their behaviour.

These “behavioural targeting strategies” involve taking time to research clients' preferences. A wide range of marketing strategies, including direct mail and email marketing can be made more effective through this targeted approach. This is according to Jenna Tool from business consultancy Overnight Print.

She explained that there are various ways to collect the information from existing and potential clients: "Companies can utilise feedback campaigns through surveys, either mailed or offered online, to see what kind of information customers want to receive and which promotions or products they are most interested in hearing about."

Evidence suggests that customers are turned off then they receive unsolicited and irrelevant marketing emails and are less likely to use a brand again if they receive this kind of marketing.

Shaft also says that detailed 'opt-in choices' are a must for any new firm thinking about sending marketing emails. They should also use these forms, together with opt-out forms, to gather information on the clients’ behaviours.