People rarely dispute Sister Mary Thomas Zinkand.
"There's no such phrase as 'No, sister,' " says Dr. Lee Russo, chief of neurosurgery at Mercy Medical Center, where the Roman Catholic nun is president and chief executive officer.
"And 'yes, sister' is all one word: 'Y-e-s-i-s-t-e-r.'
"People just fall in line behind her. There's no intimidation. You just want to do it because she's right. She's decent. There's absolutely no self-interest there at all.
"This isn't a job she's doing so she can become the president of Hopkins. This is her life."
But Sister Thomas' tenure is nearing an end. After 35 years as administrator of downtown Baltimore's Catholic-sponsored, community-oriented hospital, she is retiring at the end of this month.
She is in her 70s (she won't be more specific), and says, simply: "It's time to leave. I've been in here long enough."
Sister Helen Amos will succeed her. A member of the hospital's board of trustees for 14 years, Sister Helen is a former head of the Sisters of Mercy of the United States. The order's main work is teaching and nursing.
Sister Thomas has run Mercy Hospital since 1953, except for 1959 to 1963 when she served as administrator of Mercy Villa, a nursing home on Bellona Avenue.
She has led Mercy through tremendous changes, such as the creation of Medicare and Medicaid, federal price controls and cost-containment regulations, computerization, and a shift in emphasis from inpatient to outpatient treatment.
"No matter what the storm, no matter how difficult the circumstance, Sister Thomas has always brought a sense of calm assurance to Mercy's corporate process," board member Richard O. Berndt said last weekend at a brunch held in her honor.
Sister Thomas oversaw the renovation of Mercy's physical plant as well as the construction of new buildings. She initiated numerous health programs that serve the downtown business community and poor people throughout the city.
The hospital provides a lot of what it calls "charity care." That means people don't pay for it -- which means that making ends meet is a constant struggle, says Gary Michael, Mercy's vice president of marketing and communications.
He says the business people on the board of trustees have to keep telling Sister Thomas and the others: "Remember, sisters. No margin, no mission."
The mission statement says the hospital is to "provide and promote health services for the people of Baltimore of every creed, color, economic and social condition."
"What she does doesn't always make business sense," Mr. Michael says. "But she always says, 'It's people that count first. We've got to make sure that overrides everything.' "
By people, Sister Thomas means employees as well as patients. For a manager, Mr. Michael says, that can be frustrating.
You might confront an urgent problem, he says, and think you must talk to Sister Thomas immediately. But you can't find her, because she's in the laundry talking to a worker whose father has just died.
"That, to me, is Sister," Mr. Michael says. "Sister makes time for the things that are most important."
Margaret Brunson, a housekeeper at the hospital for 25 years, says: "If you see her in the hall and go up to talk to her, she's never too busy to talk to you."
Many of Mercy's 1,420 workers attended farewell receptions for Sister Thomas earlier this month. At the reception for the night shift, someone mentioned shortly before midnight that one employee -- the telephone operator -- couldn't stop work to attend. Sister Thomas promptly piled food on a tray and took it to the operator herself.
Examples of Sister Thomas' compassion abound.
One day in January, Sister Thomas' secretary, Jane Brown, got a phone call about noon. Ms. Brown was told that her mother, sick for some time, was dying. The secretary told her boss she must leave right away.
Sister Thomas went home with her and prayed at her mother's bedside all afternoon.
"Tell me what other president would just drop everything to do that," Ms. Brown says. "She is a living example of Christ's love, compassion and humility."
Sister Thomas, a Baltimore native, grew up in Hamilton and studied nursing at Mercy Hospital School of Nursing and Mount St. Agnes College. She decided to become a nun while a graduate nurse in pediatrics at Mercy.
She holds a master's degree in hospital administration from St. Louis University.
After all these years at the top, if she's in a morning meeting and notices no one has coffee, she gets it. If she's in a late meeting and the telephone rings, she answers it.
"She just never quite got the hang of being boss," says Dr. Russo. "Sister has never given herself any privileges.
"She's just the salt of the earth -- no pretense at all. In your heart you'd like to be like Sister when you grow up."
Sister Thomas says that after retiring she hopes to travel. But she will continue living in the convent on the hospital's 17th floor.
That means she may appear in patients' rooms, as she has for the past four decades, popping in to ask whether the care is good, the food is good, checking whether the place is clean.
She fluffs up patients' pillows and maybe says a prayer. And then she's gone, off to another room, and the patients seldom realize that the head of the hospital, one of the longest-tenured CEOs in the state, has just graced them with her presence.