A company’s existing customers are a "precious commodity" who are the "best prospect" for a firm’s next sale, according to the Local Online Marketing Association.

President of the organisation Fred Waters makes his comments in the online pages of the American Chronicle, noting that many firms are not getting the most lifetime value out of their clients by keeping in touch with them.

He states that while in the past it may have been seen as too expensive and troublesome to do this, the advent of email and the internet render this excuse invalid.

"Email is an incredibly cost-effective marketing tool. It lets you stay in touch with your customers for pennies," Mr Waters explains, noting that the medium can also be used to promote products and services.

He states that regular correspondence with customers will result in them identifying with a firm or brand and increase the chances of them sending business their way when they are ready to make a purchase.

Mr Waters’ comments echo the sentiments of web design firm Blue Tangerine Solutions, which recently identified email as one of the most cost-effective ways to generate leads and develop a brand.