Editor’s note: The healthcare e-commerce and digital services market could reach an estimated $32 billion within the next several years, says Goldman Sachs. That market potential is capturing the attention of lots of application developers and service providers that already have a base in online retailing.

In its soon-to-be published report—Healthcare E-Commerce Opportunities—Internet Health Management examines the risk and reward potential online retailers and e-commerce and web services vendors see in the digital and mobile healthcare market, and the challenges they face in building a business in healthcare.

Here’s a preview of the overall size of the market.

For many e-commerce service companies, healthcare might well be described as the holy grail of industry markets. After all, digital healthcare technology and services represents a big market, about five times bigger than the market for business-to-consumer e-commerce services. And it’s very diverse, requiring technology and services in such areas as includes e-commerce, mobile commerce and marketing, customer service, and database and customer relationship management, among others.

Forrester Research Inc. estimates that retailers of all sizes spend about $6.1 billion annually on e-commerce products and services. In comparison, healthcare organizations—including hospitals, health insurance companies, doctors, laboratories, pharmacies and drug makers—are expected to spend $32 billion annually on digital healthcare technology and related services by 2021, according to investment banker Goldman Sachs. They are spending about $10 billion now, or about 10% of the estimated $100 billion healthcare spends annually on information technology, says Goldman Sachs.

But companies seeking to sell their technology and services to healthcare organizations often encounter entrenched ways of doing business and lots of red tape. As a result, it takes careful planning, plenty of resources, and patience to make a successful run at the digital and healthcare e-commerce market, note e-commerce analysts. And not every startup or established company gets everything right the first time out.

“Getting into healthcare is not for the faint-hearted,” says Gene Alvarez, managing vice president and analyst at Gartner Inc. “It’s a big, fragmented and heavily regulated industry that takes time, money and a really well thought out strategy to pull off a new technology product or service.”

A recent survey of e-commerce vendors by Internet Retailer found 68% of respondents considered getting into the healthcare market a “very important” or “important” priority. The survey, which garnered a detailed response from 29 e-commerce technology product and services companies, also found that 54% of e-commerce vendors not already in the market have plans to begin selling their products and services to healthcare organizations, such as hospitals, doctor groups and insurers, within the next six months.