ST. LOUIS — One year after the nonprofit community cafe concept was launched in Clayton, Mo., the Panera Cares initiative still is going strong and has expanded to two other locations: Dearborn, Mich., and Portland, Ore.

Introduced by Panera Bread Co. in May 2010 through its Panera Bread Foundation, Inc., the community cafe concept encourages customers to take what they need and donate their fair share. There are no prices or cash registers, only suggested donation levels and donation bins.

“When the Foundation launched the Panera Cares concept one year ago (under the name Saint Louis Bread Co. Cares), we were not sure how people would respond,” said Ron Shaich, president of the Panera Bread Foundation and executive chairman of Panera, L.L.C. “In many ways, these cafes are a test of humanity. We didn’t know if people would help each other or take advantage. Twelve months later, we’re proud to say that people have really stepped up and helping us achieve our goal ensuring everyone who needs a meal gets one — whether or not they can afford it.”

Mr. Shaich said about 20% of visitors to the cafes leave more than the suggested amount, while 20% leave less and 60% leave the suggested donation. On average, each cafe serves 3,500 to 4,000 customers per week and generates about 75% to 80% of the retail value of the food.

“If we continue at the level of donation we’ve been experiencing, we should be able to cover all of our costs and sustain our community cafes for the long term,” he said. “To put it simply, these are nonprofit community cafes of shared responsibility. They will only survive and self-sustain in people in those communities do their part.”