A sample of a note from Greg Gardner, chief architect of defense solutions at NetApp, who writes thank y ou notes to recognize employees. (Coutesy of Greg Gardner)

Company: NetApp.

Location: Vienna. (Headquarters: Sunnyvale, Calif.)

Number of employees: 11,500.

Greg Gardner carries a stack of note cards when he travels, in case an employee catches his eye.

When one does, Gardner, chief architect of defense solutions at NetApp’s Vienna office, writes a note of thanks. He seals it in an envelope and delivers it the next day.

“They’re my teammates, and I care about them,” said Gardner, 59.

Gardner began writing thank-you notes during his 30 years in the Army. He prefers to write them with a fountain pen he’s had since the 1980s.

“When the conditions are right — when I’m at home at my desk, I take out that lovely pen,” he said. “But that’s not the only thing I use. I’ll scribble away with a ballpoint if that’s all I’ve got.”

Along the way, Gardner has set a few ground rules for himself: Notes must offer only praise, should be handwritten, and must go out within 24 hours.

Last month, he worked with Alex Kuscher at a trade show. The next morning, there was an envelope waiting on her desk.

“I kept wondering what it was,” said Kuscher, a senior marketing manager at the company. “I was like, is it for the cookies I brought in? Is it a Christmas card? I was so pleasantly surprised to be recognized for my work.”

As a colonel in The Old Guard, the battalion that conducts ceremonies for fallen soldiers, Gardner often wrote 10 notes a night. At NetApp, a data management company of 11,500 employees, he writes one or two a month.

“I don’t see people face-to-face all that often anymore,” he said. “That makes it more challenging.”

Earlier this year, Gardner ran into a soldier at Fort Meade who had something to show him: A book filled with handwritten notes from Gardner.

“That just blew me away.”