Inc. says strong growth in sales to universities like the University of Washington (above), Stanford and Penn State are helping to drive B2B and overall sales. Inc. scored high marks for the fiscal year ended Dec. 31, when it generated more than $3 billion in profit on net sales of $177.87 billion. Profit rose 28% from the prior year, revenue 31%.

A good part of that performance came from the overtures it has made in recent years to universities that have set up online procurement of supplies from Amazon’s business-to-business operations, it says.

“We continue to build our business—B2B business—and are very happy with the initial performance there with a number of companies and universities that we’ve been working with,” Brian Olsavsky, chief financial officer, said on a fourth-quarter conference call with stock analysts last week, according to a transcript from Seeking Alpha.

The merchant’s B2B unit, Amazon Business, operates procurement contracts with multiple universities, including the University of Washington, the University of Minnesota, Stanford University, Clark University, Penn State and the University of Illinois. Clark, for example, uses Jaggaer procurement software, formerly known as SciQuest, to “punch out” from Jaggaer to Amazon Business, where Clark personnel can make authorized online purchases that get recorded in Clark’s procurement and spend-management system.

A year ago, Amazon Business won a major contract to provide procurement services to schools and state and local government agencies.

Amazon Business, No. 91 in the B2B E-Commerce 300, has also added features to its website designed to help business customers manage their organization’s spending by product category and department, among other criteria.

Amazon finished the year on an even stronger note, with fourth quarter sales up 38.2% from a year earlier, to $60.45 billion. For more about Amazon’s 2017 financials, click here.